UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of August 2021

Commission File Number 001-15170

GlaxoSmithKline plc

(Translation of registrant's name into English)

980 Great West Road, Brentford, Middlesex, TW8 9GS

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F . . . .X. . . . Form 40-F . . . . . . . .

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ____

GlaxoSmithKline plc (the 'Company')

Transaction notification

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms E Walmsley
b)	Position/status	Chief Executive Officer
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Connor
b)	Position/status	President, Vaccines & Global Health
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms D Conrad
b)	Position/status	SVP, Human Resources
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr J Ford
b)	Position/status	SVP and General Counsel
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms S Jackson
b)	Position/status	SVP, Global Communications and CEO Office
c)	Initial notification/amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Jackson
b)	Position/status	PCA of Ms S Jackson (SVP, Global Communications and CEO Office)
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	9 (partnership shares)
			£14.4732	9 (matching shares)
d)	Aggregated information
	Aggregated volume Price	18 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr D Redfern
b)	Position/status	Chief Strategy Officer
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr R Simard
b)	Position/status	President, Pharmaceuticals Supply Chain
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	9 (partnership shares)
			£14.4732	9 (matching shares)
d)	Aggregated information
	Aggregated volume Price	18 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Mr P Thomson
b)	Position/status	President, Global Affairs
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms D Waterhouse
b)	Position/status	Chief Executive Officer of ViiV Healthcare
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	9 (partnership shares)
			£14.4732	9 (matching shares)
d)	Aggregated information
	Aggregated volume Price	18 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

1.	Details of PDMR/person closely associated with them ('PCA')
a)	Name	Ms V Whyte
b)	Position/status	Company Secretary
c)	Initial notification/ amendment	Initial notification
2.	Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor
a)	Name	GlaxoSmithKline plc
b)	LEI	5493000HZTVUYLO1D793
3.	Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted
a)	Description of the financial instrument	Ordinary shares of 25 pence each ('Ordinary Shares') ISIN: GB0009252882
b)	Nature of the transaction	Acquisition of Ordinary Shares under the Company's Share Reward Plan
c)	Price(s) and volume(s)		Price(s)	Volume(s)
			£14.4732	8 (partnership shares)
			£14.4732	8 (matching shares)
d)	Aggregated information
	Aggregated volume Price	16 Ordinary Shares £14.4732
e)	Date of the transaction	2021-08-10
f)	Place of the transaction	London Stock Exchange (XLON)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorised.

	GlaxoSmithKline plc
	(Registrant)
Date: August 11, 2021
	By:/s/ VICTORIA WHYTE --------------------------
	Victoria Whyte
	Authorised Signatory for and on
	behalf of GlaxoSmithKline plc