During four years with Detroit, Jones rushed for 3,067 yards and 24 touchdowns on 761 carries. Jones, who played for Virginia Tech, was drafted in the first round by Detroit in 2004, and had his best year as a rookie, rushing for 1,133 yards and five touchdowns.
Last season, Jones rushed for 581 yards and a career-high eight touchdowns on 153 carries. He also had 32 receptions for 197 yards, but tore ligaments in his right knee on Dec. 23 against Kansas City.
Detroit released him in the offseason.
"I'm ecstatic," Jones told the Chicago Tribune. "I know the situation. I know the Bears' rich history of winning. Looking at the Bears, I know they're a tough, running team. I can't wait to be a part of it."
The Bears cut starter Cedric Benson in the offseason after Benson had several run-ins with police. That left second-round draft pick Matt Forte of Tulane as the likely starter.
If his knee is healthy, the veteran Jones could beat out the rookie. Regardless, the Bears needed depth at the position.