The 1991 Youngstown State Penguins football team represented Youngstown State University in the 1991 NCAA Division I-AA football season. The Penguins were led by sixth-year head coach Jim Tressel and played their home games at Stambaugh Stadium. They finished the season 12–3. They received an at-large bid to the I-AA playoffs, where they defeated Villanova, Nevada, and Samford to advance to the National Championship Game, where they defeated Marshall. This was their first national championship in school history.

Date	Opponent	Rank	Site	TV	Result	Attendance	Source
September 7	Edinboro	No. 9	Stambaugh Stadium Youngstown, OH		W 24–0		[1]
September 14	at Delaware State	No. 8	Alumni Stadium Dover, DE		L 29–33		[2]
September 21	Morgan State		Stambaugh Stadium Youngstown, OH		W 57–22	9,313	[3]
September 28	Northeastern		Stambaugh Stadium Youngstown, OH		W 59–7		[4]
October 5	at Stephen F. Austin		Homer Bryce Stadium Nacogdoches, TX		W 16–9	8,212	[5]
October 12	at Akron	No. 18	Rubber Bowl Akron, OH (Steel Tire)		L 24–38	6,335	[6]
October 19	Liberty		Stambaugh Stadium Youngstown, OH		L 8–10		[7]
November 2	at No. 20 Georgia Southern		Paulson Stadium Statesboro, GA		W 19–17	16,461	[8]
November 9	James Madison		Stambaugh Stadium Youngstown, OH		W 28–21		[9]
November 16	Slippery Rock	No. 16	Stambaugh Stadium Youngstown, OH		W 40–21		[10]
November 23	at Towson State	No. 14	Minnegan Stadium Towson, MD		W 27–17	1,210	[11]
November 30	No. 7 Villanova	No. 13	Stambaugh Stadium Youngstown, OH (NCAA Division I-AA First Round)		W 17–16	9,556	[12]
December 7	at No. 1 Nevada	No. 13	Mackay Stadium Reno, NV (NCAA Division I-AA Quarterfinal)		W 30–28	13,476	[13]
December 14	No. 10 Samford	No. 13	Stambaugh Stadium Youngstown, OH (NCAA Division I-AA Semifinal)		W 10–0	17,033	[14]
December 21	vs. No. 8 Marshall	No. 13	Paulson Stadium Statesboro, GA (NCAA Division I-AA National Championship Game)	CBS	W 25–17	12,667	[15]
Homecoming Rankings from NCAA Division I-AA Football Committee Poll released prior to the game

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