The 1991 Appalachian State Mountaineers football team was an American football team that represented Appalachian State University as a member of the Southern Conference (SoCon) during the 1991 NCAA Division I-AA football season.
In their third year under head coach Jerry Moore, the Mountaineers compiled an overall record of 8–4 with a conference mark of 5–1.
Appalachian State was SoCon champion and advanced to the NCAA Division I-AA Football Championship playoffs, where they lost to Eastern Kentucky in the first round.
The following Mountaineers were selected in the 1992 NFL draft following the season.
This college football 1990s season article is a stub.