POS EX

As filed with the Securities and Exchange Commission on January 13, 2016

Registration Statement No. 333-203739

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C.

POST-EFFECTIVE AMENDMENT NO. 3

TO

REGISTRATION STATEMENT

UNDER

SCHEDULE B

OF

THE SECURITIES ACT OF 1933

THE KOREA DEVELOPMENT BANK

(Name of Registrant)

THE REPUBLIC OF KOREA

(Name of Co-Registrant and Guarantor)

Names and Addresses of Authorized Representatives:

Nak Joo Seong or Jin Hwan Sah Duly Authorized Representatives in the United States of The Korea Development Bank 320 Park Avenue, 32nd Floor New York, New York 10022 Suk-Kwon Na Duly Authorized Representative in the United States of The Republic of Korea 335 East 45th Street New York, New York 10017

Copies to:

Jinduk Han, Esq.

Cleary Gottlieb Steen & Hamilton LLP

c/o 37th Floor, Hysan Place

500 Hennessy Road, Causeway Bay

Hong Kong

The securities registered hereby will be offered on a delayed or continuous basis pursuant to the procedures set forth in Securities Act Release Nos. 33-6240 and 33-6424.

This Post-Effective Amendment No. 3 is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act of 1933, as amended.

EXPLANATORY NOTE

This Post-Effective Amendment No. 3 to the registrant’s Registration Statement under Schedule B (File No. 333-203739), declared effective by the Securities and Exchange Commission on June 18, 2015, is being filed solely for the purpose of filing Exhibits M–5 and M-6 to such Registration Statement pursuant to Rule 462(d) under the Securities Act. This Post-Effective Amendment No. 3 is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act of 1933, as amended. No changes or additions are being made hereby to the Prospectus which forms part of such Registration Statement.

PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 11. Estimated Expenses.*

It is estimated that our expenses in connection with the sale of the debt securities, warrants and guarantees hereunder, exclusive of compensation payable to underwriters and agents, will be as follows:

SEC Registration Fee	US$	573,000
Printing Costs		250,000
Legal Fees and Expenses		450,000
Fiscal Agent Fees and Expenses		50,000
Blue Sky Fees and Expenses		50,000
Rating Agencies’ Fees		350,000
Miscellaneous (including amounts to be paid to underwriters in lieu of reimbursement of certain expenses)		600,000
Total	US$	2,323,000

* Based on three underwritten offerings of the debt securities.

II-I

UNDERTAKINGS

The Registrants hereby undertake:

(a) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of this Registration Statement (or the most recent post-effective amendment thereto) which, individually or in the aggregate, represent a fundamental change in the information set forth in this Registration Statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in this Registration Statement or any material change to such information in this Registration Statement;

(b) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and

(c) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(d) That, for purposes of determining liability under the Securities Act of 1933 to any purchaser:

each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

(e) That, for the purpose of determining any liability under the Securities Act of 1933 to any purchaser in the initial distribution of the securities:

The undersigned registrants undertake that in a primary offering of securities of the undersigned registrants pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrants will be sellers to the purchaser and will be considered to offer or sell such securities to such purchaser;

(i) Any preliminary prospectus or prospectus of the undersigned registrants relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrants or used or referred to by the undersigned registrants;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrants or their securities provided by or on behalf of the undersigned registrants; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrants to the purchaser.

II-2

CONTENTS

This Registration Statement is comprised of:

(1) Facing Sheet.

(2) Explanatory Note.

(3) Part I, consisting of the Prospectus.

(4) Part II, consisting of pages II-1 to II-9

(5) The following Exhibits:

A-1	-	Form of Underwriting Agreement Standard Terms, incorporated herein by reference to Exhibit A to the Registration Statement of The Korea Development Bank (No. 33-38873).
B-1	-	Form of Fiscal Agency Agreement, including forms of Debt Securities, incorporated herein by reference to Exhibit B-1 to the Registration Statement of The Korea Development Bank (No. 33-44818).
B-2	-	Form of global Debt Security that bears interest at a fixed rate, incorporated herein by reference to Exhibit B-2 to the Registration Statement of The Korea Development Bank (No. 33-156305).
B-3	-	Form of Amendment No. 1 to Fiscal Agency Agreement, incorporated herein by reference to Exhibit B-3 to the Registration Statement of The Korea Development Bank (No. 333-111608).
C-1	-	Form of Warrant Agreement, including form of Warrants.*
C-2	-	Form of Guarantee Agreement, including form of Guarantees, incorporated herein by reference to Exhibit C-2 to the Registration Statement of The Korea Development Bank (No. 333-97299).
C-3	-	Form of Solicitation Indemnification Agreement, incorporated herein by reference to Exhibit C-3 to the Registration Statement of The Korea Development Bank (No. 333-97299).
D-1	-	Consent of the Chief Executive Officer & Chairman of The Korea Development Bank (included on page II-5).
D-2	-	Power of Attorney of the Chief Executive Officer & Chairman of The Korea Development Bank, incorporated herein by reference to Exhibit D-2 to the Registration Statement of The Korea Development Bank (No. 333-189409).
E-1	-	Consent of the Minister of Strategy and Finance of The Republic of Korea (included on Page II-6).
E-2	-	Power of Attorney of the Minister of Strategy and Finance of The Republic of Korea, incorporated herein by reference to Exhibit E-2 to the Registration Statement of The Korea Development Bank (No. 333-156305).
F	-	Consent of KPMG Samjong Accounting Corp.**
G-1	-	Letter appointing certain persons as authorized agents of The Korea Development Bank in the United States, incorporated herein by reference to Exhibit G-1 to the Registration Statement of The Korea Development Bank (No. 333-189409).
G-2	-	Letter appointing authorized agents of The Republic of Korea in the United States (included in Exhibit E-2), incorporated herein by reference to Exhibit G-2 to the Registration Statement of The Korea Development Bank (No. 333-189409).
H	-	The Korea Development Bank Act, incorporated herein by reference to Exhibit H to the Registration Statement of The Korea Development Bank (No. 333-197061).
I	-	The Enforcement Decree of The Korea Development Bank Act.**

II-3

J	-	The Articles of Incorporation of The Korea Development Bank.**
K-1	-	Form of Prospectus Supplement relating to The Korea Development Bank’s Medium-Term Notes, Series C, Due Not Less Than Nine Months From Date of Issue (the “Series C Notes”), incorporated herein by reference to Exhibit K-1 to the Registration Statement of The Korea Development Bank (No. 333-6866).
K-2	-	Form of Supplement to the Prospectus Supplement relating to the Korea Development Bank’s Series C Notes, incorporated herein by reference to Exhibit K-2 to the Registration Statement of The Korea Development Bank (No. 333-6866).
L	-	Form of Distribution Agreement between The Korea Development Bank and the Agents named therein relating to the offer or sale from time to time of the Series C Notes, incorporated herein by reference to Exhibit L to the Registration Statement of The Korea Development Bank (No. 333-6866).
M-1	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, c/o 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of the Debt Securities (with or without Warrants).**
M-2	-	Opinion (including consent) of Kim & Chang, 39, Sajik-ro 8-gil, Jongno-gu, Seoul, Korea, Korean counsel to The Korea Development Bank, in respect of the legality of the Debt Securities (with or without Warrants) and the Guarantees to be issued by The Republic of Korea.**
M-3	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.25% Notes due 2020.**
M-4	-	Opinion (including consent) of Hwang Mok Park P.C., 9th Floor, Shinhan Bank Building, 20, Sejong-daero 9-gil, Jung-gu, Seoul 100-724, The Republic of Korea, Korean counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.25% Notes due 2020.**
M-5	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.50% Notes due 2021 and US$1,000,000,000 3.00% Notes due 2026.
M-6	-	Opinion (including consent) of Kim & Chang, 39, Sajik-ro 8-gil, Jongno-gu, Seoul, Korea, Korean counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.50% Notes due 2021 and US$1,000,000,000 3.00% Notes due 2026.
N-1	-	Form of the Series C Note that bears interest at a fixed rate, incorporated herein by reference to Exhibit N-1 to the Registration Statement of The Korea Development Bank (No. 333-6866).
N-2	-	Form of the Series C Note that bears interest at a floating rate, incorporated herein by reference to Exhibit N-2 to the Registration Statement of The Korea Development Bank (No. 333-6866).
O	-	Form of Calculation Agency Agreement between The Korea Development Bank and the calculation agent named therein relating to the Series C Notes that bear interest at a floating rate, incorporated herein by reference to Exhibit O to the Registration Statement of The Korea Development Bank (No. 333-6866).

* May be filed by amendment.

** Previously filed.

II-4

SIGNATURE OF THE KOREA DEVELOPMENT BANK

Pursuant to the requirements of the Securities Act of 1933, as amended, The Korea Development Bank has duly caused this Registration Statement or amendment thereto to be signed on its behalf by the undersigned, thereunto duly authorized, in Seoul, The Republic of Korea, on the 13th day of January, 2016.

THE KOREA DEVELOPMENT BANK
By:	KYTTACK HONG*†
	Chief Executive Officer & Chairman
†By:	/S/ SANG PIL KO
	Sang Pil Ko
	(Attorney-in-fact)

* Consent is hereby given to use of his name in connection with the information specified in this Registration Statement or amendment thereto to have been supplied by him and stated on his authority.

II-5

SIGNATURE OF THE REPUBLIC OF KOREA

Pursuant to the requirements of the Securities Act of 1933, as amended, The Republic of Korea has duly caused this Registration Statement or amendment thereto to be signed on its behalf by the undersigned, thereunto duly authorized, in The City of New York, New York, on the 13th day of January, 2016.

THE REPUBLIC OF KOREA
By:	Kyung Hwan Choi*†
	Minister of Strategy and Finance
†By:	/s/ SUK-KWON NA
	Suk-Kwon Na
	(Attorney-in-fact)

* Consent is hereby given to use of his name in connection with the information specified in this Registration Statement or amendment thereto to have been supplied by him and stated on his authority.

II-6

SIGNATURE OF AUTHORIZED REPRESENTATIVE

OF THE KOREA DEVELOPMENT BANK

Pursuant to the Securities Act of 1933, as amended, the undersigned, a duly authorized representative in the United States of The Korea Development Bank, has signed this Registration Statement or amendment thereto in The City of New York, New York, on the 13th day of January, 2016.

†By:	/S/ Nak Joo Seong
	Nak Joo Seong
	New York Branch
	The Korea Development Bank

II-7

SIGNATURE OF AUTHORIZED REPRESENTATIVE

OF THE KOREA DEVELOPMENT BANK

Pursuant to the Securities Act of 1933, as amended, the undersigned, a duly authorized representative in the United States of The Korea Development Bank, has signed this Registration Statement or amendment thereto in The City of New York, New York, on the 13th day of January, 2016.

†By:	/S/ Jin Hwan Sah
	Jin Hwan Sah
	New York Branch
	The Korea Development Bank

II-8

SIGNATURE OF AUTHORIZED REPRESENTATIVE

OF THE REPUBLIC OF KOREA

Pursuant to the Securities Act of 1933, as amended, the undersigned, a duly authorized representative in the United States of The Republic of Korea, has signed this Registration Statement or amendment thereto in The City of New York, New York, on the 13th day of January, 2016.

†By:	/S/ SUK-KWON NA
	Suk-Kwon Na
	Financial Attaché
	Korean Consulate General in New York

II-9

EXHIBIT INDEX

A-1	-	Form of Underwriting Agreement Standard Terms, incorporated herein by reference to Exhibit A to the Registration Statement of The Korea Development Bank (No. 33-38873).
B-1	-	Form of Fiscal Agency Agreement, including forms of Debt Securities, incorporated herein by reference to Exhibit B-1 to the Registration Statement of The Korea Development Bank (No. 33-44818).
B-2	-	Form of global Debt Security that bears interest at a fixed rate, incorporated herein by reference to Exhibit B-2 to the Registration Statement of The Korea Development Bank (No. 33-156305).
B-3	-	Form of Amendment No. 1 to Fiscal Agency Agreement, incorporated herein by reference to Exhibit B-3 to the Registration Statement of The Korea Development Bank (No. 333-111608).
C-1	-	Form of Warrant Agreement, including form of Warrants.*
C-2	-	Form of Guarantee Agreement, including form of Guarantees, incorporated herein by reference to Exhibit C-2 to the Registration Statement of The Korea Development Bank (No. 333-97299).
C-3	-	Form of Solicitation Indemnification Agreement, incorporated herein by reference to Exhibit C-3 to the Registration Statement of The Korea Development Bank (No. 333-97299).
D-1	-	Consent of the Chief Executive Officer & Chairman of The Korea Development Bank (included on page II-5).
D-2	-	Power of Attorney of the Chief Executive Officer & Chairman of The Korea Development Bank, incorporated herein by reference to Exhibit D-2 to the Registration Statement of The Korea Development Bank (No. 333-189409).
E-1	-	Consent of the Minister of Strategy and Finance of The Republic of Korea (included on Page II-6).
E-2	-	Power of Attorney of the Minister of Strategy and Finance of The Republic of Korea, incorporated herein by reference to Exhibit E-2 to the Registration Statement of The Korea Development Bank (No. 333-156305).
F	-	Consent of KPMG Samjong Accounting Corp.**
G-1	-	Letter appointing certain persons as authorized agents of The Korea Development Bank in the United States, incorporated herein by reference to Exhibit G-1 to the Registration Statement of The Korea Development Bank (No. 333-189409).
G-2	-	Letter appointing authorized agents of The Republic of Korea in the United States (included in Exhibit E-2).
H	-	The Korea Development Bank Act, incorporated herein by reference to Exhibit H to the Registration Statement of The Korea Development Bank (No. 333-197061).
I	-	The Enforcement Decree of The Korea Development Bank Act.**
J	-	The Articles of Incorporation of The Korea Development Bank.**
K-1	-	Form of Prospectus Supplement relating to The Korea Development Bank’s Medium-Term Notes, Series C, Due Not Less Than Nine Months From Date of Issue (the “Series C Notes”), incorporated herein by reference to Exhibit K-1 to the Registration Statement of The Korea Development Bank (No. 333-6866).
K-2	-	Form of Supplement to the Prospectus Supplement relating to the Korea Development Bank’s Series C Notes, incorporated herein by reference to Exhibit K-2 to the Registration Statement of The Korea Development Bank (No. 333-6866).

L	-	Form of Distribution Agreement between The Korea Development Bank and the Agents named therein relating to the offer or sale from time to time of the Series C Notes, incorporated herein by reference to Exhibit L to the Registration Statement of The Korea Development Bank (No. 333-6866).
M-1	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, c/o 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of the Debt Securities (with or without Warrants).**
M-2	-	Opinion (including consent) of Kim & Chang, Sajik-ro 8-gil, Jongno-gu, Seoul, Korea, Korean counsel to The Korea Development Bank, in respect of the legality of the Debt Securities (with or without Warrants) and the Guarantees to be issued by The Republic of Korea.**
M-3	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.25% Notes due 2020.**
M-4	-	Opinion (including consent) of Hwang Mok Park P.C., 9th Floor, Shinhan Bank Building, 20, Sejong-daero 9-gil, Jung-gu, Seoul 100-724, The Republic of Korea, Korean counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.25% Notes due 2020.**
M-5	-	Opinion (including consent) of Cleary Gottlieb Steen & Hamilton LLP, 37th Floor, Hysan Place, 500 Hennessy Road, Causeway Bay, Hong Kong, United States counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.50% Notes due 2021 and US$1,000,000,000 3.00% Notes due 2026.
M-6	-	Opinion (including consent) of Kim & Chang, 39, Sajik-ro 8-gil, Jongno-gu, Seoul, Korea, Korean counsel to The Korea Development Bank, in respect of the legality of The Korea Development Bank’s US$500,000,000 2.50% Notes due 2021 and US$1,000,000,000 3.00% Notes due 2026..
N-1	-	Form of the Series C Note that bears interest at a fixed rate, incorporated herein by reference to Exhibit N-1 to the Registration Statement of The Korea Development Bank (No. 333-6866).
N-2	-	Form of the Series C Note that bears interest at a floating rate, incorporated herein by reference to Exhibit N-2 to the Registration Statement of The Korea Development Bank (No. 333-6866).
O	-	Form of Calculation Agency Agreement between The Korea Development Bank and the calculation agent named therein relating to the Series C Notes that bear interest at a floating rate, incorporated herein by reference to Exhibit O to the Registration Statement of The Korea Development Bank (No. 333-6866).

* May be filed by amendment.

** Previously filed.

EX-99.(M)(5)

Exhibit M-5

[Cleary Gottlieb Steen & Hamilton LLP Letterhead]

January 13, 2016

The Korea Development Bank

14, Eunhaeng-ro

Yeongdeungpo-gu

Seoul 07242

The Republic of Korea

Ladies and Gentlemen:

We have acted as special United States counsel to The Korea Development Bank, a statutory juridical entity established in the Republic of Korea under The Korea Development Bank Act of 1953, as amended (the “Bank”) in connection with the Bank’s offering pursuant to a registration statement under Schedule B (No. 333- 203739) of US$500,000,000 aggregate principal amount of its 2.50% notes due 2021 (the “2021 Notes”) and US$1,000,000,000 aggregate principal amount of its 3.00% notes due 2026 (the “2026 Notes” and, together with the 2021 Notes, the “Notes”) to be issued under a fiscal agency agreement dated as of February 15, 1991 as amended by Amendment No. 1 thereto dated as of June 25, 2004 (the “Fiscal Agency Agreement”) between the Bank and The Bank of New York Mellon, as fiscal agent. Such registration statement, as amended when it became effective, is herein called the “Registration Statement;” the related prospectus dated June 18, 2015, as filed with the Securities and Exchange Commission (the “Commission”) pursuant to Rule 424(b) under the Securities Act of 1933, as amended (the “Securities Act”), is herein called the “Base Prospectus;” the related prospectus supplement dated January 6, 2016, as filed with the Commission pursuant to Rule 424(b) under the Securities Act, is herein called the “Prospectus Supplement;” and the Base Prospectus and the Prospectus Supplement, together, are herein called the “Prospectus.”

In arriving at the opinion expressed below, we have reviewed the following documents:

(a) the Registration Statement;

(b) the Prospectus;

(c) specimens of the Notes; and

(d) an executed copy of the Fiscal Agency Agreement.

In addition, we have reviewed the originals or copies certified or otherwise identified to our satisfaction of all such records of the Bank and such other documents, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinion expressed below.

In rendering the opinion expressed below, we have assumed the authenticity of all documents submitted to us as originals and the conformity to the originals of all documents submitted to us as copies. In addition, we have assumed and have not verified (i) the accuracy as to factual matters of each document we have reviewed and (ii) that the Notes conform to the specimens thereof that we have reviewed and have been duly authenticated in accordance with the terms of the Fiscal Agency Agreement.

Based on the foregoing, and subject to the further assumptions and qualifications set forth below, it is our opinion that the Notes are the valid, binding and enforceable obligations of the Bank, entitled to the benefit of the Fiscal Agency Agreement.

In connection with the foregoing opinion, (a) we have assumed that each of the Bank and the Fiscal Agent has satisfied those legal requirements that are applicable to it to the extent necessary to make the Fiscal Agency Agreement and the Notes enforceable against it (except that no such assumption is made as to the Bank regarding matters of the federal law of the United States of America or the law of the State of New York that in our experience normally would be applicable with respect to the Fiscal Agency Agreement and the Notes), (b) such opinion is subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity and (c) such opinion is subject to the effect of judicial application of foreign laws or foreign governmental actions affecting creditors’ rights. In addition, we note that (i) the enforceability of the waiver of immunities by the Bank set forth in the Notes is subject to the limitations imposed by the Foreign Sovereign Immunities Act of 1976 and (ii) the designation of the U.S. federal courts sitting in The City of New York as a venue for actions or proceedings relating to the Notes is (notwithstanding the waiver in such provisions) subject to the power of such courts to transfer actions pursuant to 28 U.S.C. § 1404(a) or to dismiss such actions or proceedings on the grounds that such federal court is an inconvenient forum for such action or proceeding. We express no opinion as to the subject matter jurisdiction of any United States federal court to adjudicate any action relating to the Notes where jurisdiction based on diversity of citizenship under 28 U.S.C. §1332 does not exist.

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The foregoing opinion is limited to the federal law of the United States of America and the law of the State of New York.

We hereby consent to the filing of this opinion letter as an exhibit to the Registration Statement and to the reference to us under the heading “Legal Matters” in the Prospectus. In giving such consent, we do not thereby admit that we are experts with respect to any part of the Registration Statement, including this exhibit, within the meaning of the term “expert” as used in the Securities Act, or the rules and regulations of the Commission issued thereunder. We assume no obligation to advise you, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinion expressed herein.

Very truly yours,
CLEARY GOTTLIEB STEEN & HAMILTON LLP
By	/s/ Jinduk Han
	Jinduk Han, a Partner

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EX-99.(M)(6)

Exhibit M-6

[Kim & Chang Letterhead]

The Korea Development Bank

14, Eunhaeng-ro

Yeongdeungpo-gu, Seoul 07242

The Republic of Korea

Re: The Korea Development Bank

Ladies and Gentlemen:

We have acted as Korean legal counsel for The Korea Development Bank (“KDB”), a statutory juridical entity established in the Republic of Korea (“Korea”) under the Korea Development Bank Act of 1953, as amended (the “KDB Act”), in connection with KDB’s offering pursuant to a registration statement (file number: 333-203739) under Schedule B of the Securities Act of 1933, as amended (the “Securities Act”) (the “Registration Statement”) of US$500,000,000 2.50% Notes due 2021 (the “2021 Notes”) and US$1,000,000,000 3.00% Notes due 2026 (the “2026 Notes”, together with the 2021 Notes, the “Notes”) to be issued under the Fiscal Agency Agreement dated February 15, 1991, as amended by Amendment No. 1 thereto dated as of June 25, 2004, and entered into by and between KDB and the fiscal agent named therein (the “Fiscal Agency Agreement”).

In connection with providing legal opinions set forth herein, we have examined originals or copies, certified or otherwise identified to our satisfaction, of the documents, records, certificates of public officials and other instruments as we have deemed necessary or advisable. In such examination, we have assumed the genuineness of all signatures, stamps and seals, the legal capacity of natural persons, the authenticity, accuracy and up-to-datedness of all documents submitted to us as originals and the conformity to original documents of all documents submitted to us as certified or photostatic copies. As to any facts material to the opinions set forth herein, which we did not independently establish or verify, we have relied upon statements and representations of officials and other representatives of KDB.

In addition, and without prejudice to the generality of the immediately preceding paragraph, in arriving at the opinion expressed below, we have examined the following specific documents relating to the Notes:

(a) the Registration Statement;

(b) the Prospectus dated June 18, 2015 as supplemented by the Prospectus Supplement dated January 6, 2016 relating to the Notes (collectively, the “Prospectus”);

(c) an executed copy of the Fiscal Agency Agreement;

(d) a copy of the executed and authenticated 2021 Notes in global form;

(e) a copy of the executed and authenticated 2026 Notes in global form;

(f) a copy of the portion of the board of directors’ approval for the KDB fiscal year 2016 Business Plan as of December 30, 2015 including foreign currency denominated securities;

(g) copies of the articles of incorporation and the commercial registry extracts;

(h) a copy of the internal approval granted by the Chairman and CEO of KDB on December 23, 2015 authorizing the issue of the Notes;

(i) copies of specimen signatures of the authorized signatories of KDB and

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(j) a copy of the report submitted to and accepted by the Ministry of Strategy and Finance as of December 23, 2015 regarding the issuance of the Notes by KDB.

Our opinion is limited to matters governed by the laws of Korea in force at the date hereof and we do not express any opinion on any matters governed by or construed in accordance with the laws of any other jurisdiction.

Based upon the foregoing and subject to further qualifications set forth below, it is our opinion that:

1. KDB is a statutory juridical entity duly established under the KDB Act and validly existing under the laws of Korea, with power and authority to own its properties and conduct its business as described in the Prospectus forming a part of the Registration Statement;

2. The Fiscal Agency Agreement has been duly authorized and executed by KDB;

3. The statements in the Prospectus concerning matters of Korean law (except for the financial statements and related schedules and other financial and statistical data contained therein as to which we express no opinion) are accurate and up-to-date as of the date hereof in all material respects; and

4. The Notes have been duly authorized, executed, issued and delivered by KDB and constitute valid, binding and enforceable obligations of KDB.

The opinions set forth above are subject to the following qualifications: (a) the obligations of KDB under the Notes and the Fiscal Agency Agreement and the enforcement thereof may be limited or affected by laws governing bankruptcy, insolvency, fraudulent conveyance, liquidation, composition, rehabilitation, moratorium, corporate restructuring or other similar laws of Korea (including, without limitation, the Law Concerning the Restructuring of the Finance Industry), which generally affect the rights of creditors or creditor financial institutions; (b) the obligations of KDB under the Notes and the Fiscal Agency Agreement and the enforcement thereof may be also affected or limited by the general principle of good morals and other social order and the general principle of good faith and fairness provided for in the Civil Code of Korea.

We hereby consent to the use of this opinion as an exhibit to the Registration Statement and to the reference to us under the heading “Legal Matters” in the Registration Statement, without thereby admitting that we are “experts” under the Securities Act or the rules and regulations of the U.S. Securities and Exchange Commission thereunder for the purpose of any part of the Registration Statement, including the exhibit as which this opinion is filed.

Very truly yours,

/s/ Kim & Chang

Kim & Chang

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