Leshoure, a second-team All-American, rushed for a school-record 1,697 yards and 17 touchdowns last season for Illinois.
"I think I can bring versatility and leadership to an offense, especially for my position," Leshoure, who's 6-foot and 227 pounds, told the Lions' website. "I feel like I can run in between the tackles, but I can also run outside of the tackles and hit the perimeters at times to make guys miss.
"I think the thing that sets me apart from the other running backs is my ability to catch the ball. Whether it's swing routes, or five- (to) 10-yard routes or even downfield, I'm very confident with my hands."