| Oct 4, 1991 | BYU 38, Utah State 12 | Box score |
| Oct 5, 1991 | Air Force 51, Wyoming 28 | Box score |
| Oct 5, 1991 | Arizona State 21, Utah 15 | Box score |
| Oct 5, 1991 | Arkansas 22, TCU 21upset | Box score |
| Oct 5, 1991 | 11Baylor 38, Houston 21 | Box score |
| Oct 5, 1991 | Bowling Green 17, Central Michigan 10 | Box score |
| Oct 5, 1991 | 18California 27, 24UCLA 24 | Box score |
| Oct 5, 1991 | Cincinnati 30, Louisville 7upset | Box score |
| Oct 5, 1991 | Colorado State 23, UTEP 18 | Box score |
| Oct 5, 1991 | Duke 17, Vanderbilt 13 | Box score |
| Oct 5, 1991 | East Carolina 56, Akron 20 | Box score |
| Oct 5, 1991 | Eastern Michigan 21, Kent State 20 | Box score |
| Oct 5, 1991 | 13Florida 16, LSU 0 | Box score |
| Oct 5, 1991 | 1Florida State 46, 10Syracuse 14 | Box score |
| Oct 5, 1991 | Fresno State 94, New Mexico 17 | Box score |
| Oct 5, 1991 | Georgia 27, 6Clemson 12upset | Box score |
| Oct 5, 1991 | 22Illinois 24, Minnesota 3 | Box score |
| Oct 5, 1991 | Indiana 31, Michigan State 0 | Box score |
| Oct 5, 1991 | Long Beach State 31, UNLV 19 | Box score |
| Oct 5, 1991 | Louisiana Tech 37, Northern Illinois 3 | Box score |
| Oct 5, 1991 | 2Miami 40, Oklahoma State 3 | Box score |
| Oct 5, 1991 | Miami (OH) 27, Louisiana 14 | Box score |
| Oct 5, 1991 | 7Michigan 43, 9Iowa 24 | Box score |
| Oct 5, 1991 | Ole Miss 35, Kentucky 14 | Box score |
| Oct 5, 1991 | Missouri 31, Memphis 21 | Box score |
| Oct 5, 1991 | 19NC State 28, 21Georgia Tech 21 | Box score |
| Oct 5, 1991 | 8Notre Dame 42, Stanford 26 | Box score |
| Oct 5, 1991 | 14Ohio State 31, Wisconsin 16 | Box score |
| Oct 5, 1991 | 5Oklahoma 29, Iowa State 8 | Box score |
| Oct 5, 1991 | Oregon 29, New Mexico State 6 | Box score |
| Oct 5, 1991 | Pacific 56, Cal State Fullerton 28 | Box score |
| Oct 5, 1991 | 12Penn State 24, Temple 7 | Box score |
| Oct 5, 1991 | 17Pittsburgh 24, Maryland 20 | Box score |
| Oct 5, 1991 | Purdue 17, Northwestern 14 | Box score |
| Oct 5, 1991 | Rutgers 14, Army 12 | Box score |
| Oct 5, 1991 | San Diego State 47, Hawai’i 21 | Box score |
| Oct 5, 1991 | SMU 31, Tulane 17 | Box score |
| Oct 5, 1991 | Southern Miss 10, 16Auburn 9upset | Box score |
| Oct 5, 1991 | Texas 28, Rice 7 | Box score |
| Oct 5, 1991 | 23Texas A&M 37, Texas Tech 14 | Box score |
| Oct 5, 1991 | Toledo 17, Ohio 13 | Box score |
| Oct 5, 1991 | Virginia 31, Kansas 19 | Box score |
| Oct 5, 1991 | Virginia Tech 20, West Virginia 14 | Box score |
| Oct 5, 1991 | 3Washington 54, Arizona 0 | Box score |
| Oct 5, 1991 | Washington State 55, Oregon State 7 | Box score |
| Oct 5, 1991 | Western Michigan 25, Ball State 16 | Box score |