UNITED STATES SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES

EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported) November 1, 2017

MDU Resources Group, Inc.

(Exact name of registrant as specified in its charter)

Delaware	1-03480	41-0423660
(State or other jurisdiction of	(Commission File Number)	(I.R.S. Employer Identification No.)
incorporation)

1200 West Century Avenue

P.O. Box 5650

Bismarck, North Dakota 58506-5650

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including area code (701) 530-1000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.

Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 2.02. Results of Operations and Financial Condition and

Item 7.01. Regulation FD Disclosure.

On November 1, 2017, MDU Resources Group, Inc. (the "Company") issued a press release announcing third quarter 2017 earnings. A copy of the press release, which the Company is furnishing to the Securities and Exchange Commission, is attached as Exhibit 99 and incorporated by reference herein.

Item 9.01. Financial Statements and Exhibits.

(d)    Exhibits

99    Press release issued November 1, 2017, regarding third quarter 2017 earnings.

2

SIGNATURE

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 hereunto duly authorized.

MDU RESOURCES GROUP, INC.

Date November 1, 2017 By /s/ Stephanie A. Barth

Stephanie A. Barth

Vice President, Chief Accounting

Officer and Controller

3

EXHIBIT INDEX

Exhibit Number Description of Exhibit

99 Press release issued November 1, 2017, regarding third quarter 2017 earnings.

4