The 2015 Conference USA football season was part of the 2015 NCAA Division I FBS football season and played from August 2015 through January 2016.

The 2015 football season marked the 21st season of the Conference USA's existence and 20th of football competition; although C-USA was established in 1995, it did not begin football competition until 1996.

Marshall won the conference championship for the first time in the conference, defeating Louisiana Tech 26–23.

[1] The Charlotte 49ers were a transitional Division I FBS member, joining from the FCS Atlantic 10 Conference.

They replaced UAB in the East division for the 2015 season.