The 28-year-old, part of the Wanderers' side which secured promotion to the top-flight last season, should go straight into the Rangers squad for Tuesday's trip to Nottingham Forest in the Championship.
Speaking on the QPR web site Hill said "Every footballer wants to be playing games and unfortunately I wasn't getting that at Wolves, QPR have given me the opportunity to do that so I am delighted to join."
Rangers Boss Mick Harford "I just felt we needed to strengthen our back four and this is a quality signing
Source: Team Talk