Collins replaces Matt Rhule, who was hired at Baylor after four seasons with the Owls.
"We will compete for championships, we will provide a world-class student-athlete experience and education, and we will represent the community with pride," said Collins, who has been a defensive coordinator for the past seven seasons combined at Florida (2015-16), Mississippi State (2011-14) and Florida International (2010).
Collins, 45, had just completed the second year of a three-year deal with the Gators.
He will be the Owls' fourth coach in eight seasons, and all had no previous head-coaching experience before taking the job. Before Rhule, Temple's two previous coaches were Steve Addazio and Al Golden.
In the past two years under Collins, the Gators ranked sixth and seventh nationally in total defense.
"They're going to get a guy that motivates players, a guy that really understands the game and understands both sides of the ball, not just the defensive side," Florida coach Jim McElwain said. "He's done a great job of studying the offensive side and the things that it takes there. A relentless, competitive recruiter, and a guy that's now been around at some places to see how he can establish his own kind of way of doing things.
"We're really excited about the opportunity for him and his family at Temple. It's a place that's really done a great job, and he'll carry that on."
Collins also has been an assistant at UCF, Georgia Tech, Western Carolina, Albright College and Fordham. He was Alabama's director of player personnel in 2007.
Assistant Ed Foley will coach the Owls against Wake Forest in the Military Bowl on Dec. 27. Temple (10-2) is trying win 11 games for the first time in program history.
ESPN staff writer Brett McMurphy and the Associated Press contributed to this report.