    <SEC-DOCUMENT>0001193125-25-330953-index.html : 20251223
    <SEC-HEADER>0001193125-25-330953.hdr.sgml : 20251223
    <ACCEPTANCE-DATETIME>20251223161559
    ACCESSION NUMBER:		0001193125-25-330953
    CONFORMED SUBMISSION TYPE:	N-CSR
    PUBLIC DOCUMENT COUNT:		15
    CONFORMED PERIOD OF REPORT:	20251031
    FILED AS OF DATE:		20251223
    DATE AS OF CHANGE:		20251223
    EFFECTIVENESS DATE:		20251223

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			Duff & Phelps Utility & Infrastructure Fund Inc.
    		CENTRAL INDEX KEY:			0001515671
    		ORGANIZATION NAME:
    		EIN:				452261437
    		FISCAL YEAR END:			1031

    	FILING VALUES:
    		FORM TYPE:		N-CSR
    		SEC ACT:		1940 Act
    		SEC FILE NUMBER:	811-22533
    		FILM NUMBER:		251600779

    	BUSINESS ADDRESS:
    		STREET 1:		10 SOUTH WACKER DRIVE
    		STREET 2:		SUITE 1900
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606
    		BUSINESS PHONE:		(866) 270-7598

    	MAIL ADDRESS:
    		STREET 1:		10 SOUTH WACKER DRIVE
    		STREET 2:		SUITE 1900
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	Duff & Phelps Global Utility Income Fund Inc.
    		DATE OF NAME CHANGE:	20110627

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	Duff & Phelps Global Utility & Midstream Energy Income Fund Inc.
    		DATE OF NAME CHANGE:	20110316
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>N-CSR
    <SEQUENCE>1
    <FILENAME>d79889dncsr.htm
    <DESCRIPTION>N-CSR
    <TEXT>
    Document 1 - file: d79889dncsr.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(A)(1)
    <SEQUENCE>2
    <FILENAME>d79889dex99a1.htm
    <DESCRIPTION>CODE OF ETHICS
    <TEXT>
    Document 2 - file: d79889dex99a1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(A)(3)
    <SEQUENCE>3
    <FILENAME>d79889dex99a3.htm
    <DESCRIPTION>CERTIFICATION PURSUANT TO SECTION 302
    <TEXT>
    Document 3 - file: d79889dex99a3.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(A)(5)
    <SEQUENCE>4
    <FILENAME>d79889dex99a5.htm
    <DESCRIPTION>INDEPENDENT PUBLIC ACCOUNTING FIRM CHANGE
    <TEXT>
    Document 4 - file: d79889dex99a5.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(B)
    <SEQUENCE>5
    <FILENAME>d79889dex99b.htm
    <DESCRIPTION>EX-99.(B)
    <TEXT>
    Document 5 - file: d79889dex99b.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(C)
    <SEQUENCE>6
    <FILENAME>d79889dex99c.htm
    <DESCRIPTION>REGISTRANTS NOTICES
    <TEXT>
    Document 6 - file: d79889dex99c.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>7
    <FILENAME>g79889img2bc81d324.gif
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 7 - file: g79889img2bc81d324.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>8
    <FILENAME>g79889img5449628f5.gif
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 8 - file: g79889img5449628f5.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>g79889img5d7beb982.gif
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: g79889img5d7beb982.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>g79889img7627945c3.gif
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: g79889img7627945c3.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>g79889imgcdf4b0576.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: g79889imgcdf4b0576.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>g79889imgea3559b81.gif
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: g79889imgea3559b81.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>13
    <FILENAME>g79889page31.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: g79889page31.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>g79889page31b.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 14 - file: g79889page31b.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>15
    <FILENAME>g79889page31c.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 15 - file: g79889page31c.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>