The Israel international has not had a club since leaving Portsmouth in the summer and last season represented the South Coast side in the Championship.
However, manager Harry Redknapp invited the former Chelsea defender in for training at QPR and has signed him until the end of the current campaign.
"He's not in it for the money," Redknapp said. "He just wants to come in, get games, work hard and do his best."
Ben Haim also counts Bolton, Manchester City, Sunderland and West Ham among his former clubs and the 30-year-old has made 178 league appearances in England.