Joseph Cassidy Glenn (born March 7, 1949) is a former American football coach and former player.
He was the head football coach at the University of South Dakota, his alma mater, from 2012 to 2015.
He was named head coach on December 5, 2011 after the school's athletic director, David Sayler, fired Ed Meierkort.
Glenn served as the head football coach at Doane College (1976–1979), the University of Northern Colorado (1989–1999), the University of Montana (2000–2002), and the University of Wyoming (2003–2008).
He won two NCAA Division II Football Championships at Northern Colorado, in 1996 and 1997, and an NCAA Division I-AA Football Championship at Montana in 2001.