The Trojans were led by third-year head coach Lane Kiffin, played their home games at Los Angeles Memorial Coliseum, and were members of the South Division of the Pac-12 Conference.

USC returned 18 starters and 13 All-Conference performers from a team that finished the 2011 season ranked No.

They started the season ranked #1 in the AP Poll, but finished unranked—the first team to do so since the 1964 Ole Miss Rebels[1] and the first to do so in the BCS-era.

On December 22, 2011, All-American quarterback Matt Barkley announced that he would be returning to USC for his senior season to complete some "unfinished business" for the Trojans.

[2] Along with Barkley, who was a leading Heisman candidate,[3][4] the Trojan offense returns nine starters, including 2011 All-Conference center Khaled Holmes, a thousand-yard rusher from 2011 in senior running back Curtis McNeal, and two thousand-yard receivers in Robert Woods and Marqise Lee.

In addition, former Penn State running back Silas Redd transferred to USC and will be immediately eligible to play during the 2012 season.

[5] The addition of Redd means the USC offense now boasts two thousand-yard rushers, two thousand-year receivers, and a 3,500-yard passer from the 2011 season.

Kalil is expected to be succeeded at left offensive tackle by true sophomore Aundrey Walker.

[9] The Trojans also graduated defensive tackles DaJohn Harris and Christian Tupou, who are expected to be replaced in the starting lineup by sophomore George Uko and redshirt freshman Antwaun Woods.

[10] On July 30, starting Left Defensive End Devon Kennard underwent surgery for a torn pectoralis major muscle.

[11] Team doctors told him that it would take approximately four months to fully recover from the surgery, which would make him a redshirt candidate and allow him to return to USC for a fifth year in 2013.

On July 31, former Penn State running back Silas Redd announced his intent to transfer to USC in the wake of the NCAA sanctions given to the Nittany Lions relating to the Penn State child sex abuse scandal.

[12] USC returns 18 starters in 2012, including nine on offense, seven on defense, and both the starting kicker and punter.

These early enrollments included: defensive end Morgan Breslin from Diablo Valley Community College, linebacker Scott Starr from Norco High School, and offensive tackle Chad Wheeler from Santa Monica High School.

Safety/cornerback Joshua Shaw, who started three games at free safety for Florida in 2011, transferred to USC in the spring.

USC beat Colorado, 42–17, in 2011 with Matt Barkley setting a school record with six touchdown passes.

Both Matt Barkley and Robert Woods had record setting days as the Trojans cruised to a 50–6 victory.

Reports surfaced weeks after the game of a postgame altercation in the locker room which may have started over the younger players criticizing Matt Barkley for not playing in the game and his leadership in general, which led to several upperclassmen, including T.J. McDonald, coming to his defense.