Denver announced the deal on Friday.
Walker signed with the Houston Texans as a free agent in 2007 and played four games, rushing for 264 yards on 58 carries and catching 13 passes for 81 yards.
The Broncos took running back Knowshon Moreno in the first-round of last month's draft. Denver has also signed veterans J.J. Arrington, Correll Buckhalter and LaMont Jordan this offseason.
Copyright 2009 by The Associated Press