    <SEC-DOCUMENT>0000067716-21-000019-index.html : 20210326
    <SEC-HEADER>0000067716-21-000019.hdr.sgml : 20210326
    <ACCEPTANCE-DATETIME>20210326113039
    ACCESSION NUMBER:		0000067716-21-000019
    CONFORMED SUBMISSION TYPE:	DEFA14A
    PUBLIC DOCUMENT COUNT:		3
    FILED AS OF DATE:		20210326
    DATE AS OF CHANGE:		20210326

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MDU RESOURCES GROUP INC
    		CENTRAL INDEX KEY:			0000067716
    		STANDARD INDUSTRIAL CLASSIFICATION:	MINING, QUARRYING OF NONMETALLIC MINERALS (NO FUELS) [1400]
    		IRS NUMBER:				301133956
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		DEFA14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-03480
    		FILM NUMBER:		21775721

    	BUSINESS ADDRESS:
    		STREET 1:		1200 WEST CENTURY AVENUE
    		CITY:			BISMARCK
    		STATE:			ND
    		ZIP:			58503
    		BUSINESS PHONE:		701-530-1000

    	MAIL ADDRESS:
    		STREET 1:		1200 WEST CENTURY AVENUE
    		CITY:			BISMARCK
    		STATE:			ND
    		ZIP:			58503

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	MONTANA DAKOTA UTILITIES CO
    		DATE OF NAME CHANGE:	19850429
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEFA14A
    <SEQUENCE>1
    <FILENAME>a2021proxynotice-nextgen.htm
    <DESCRIPTION>MDU RESOURCES GROUP, INC. 2021 PROXY NOTICE
    <TEXT>
    Document 1 - file: a2021proxynotice-nextgen.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>notice-2x011a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: notice-2x011a.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>notice-2x021a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: notice-2x021a.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>