Ben Haim, 31, was signed by Rangers boss Harry Redknapp in the January transfer window but has made just seven appearances since as the R's slipped out of the Barclays Premier League.
Toronto are managed by former Loftus Road favourite Ryan Nelsen and Israel international Ben Haim will remain on loan at the club until the end of June.
Nelsen has already returned once to Rangers since his move to the MLS club, signing winger Hogan Ephraim on a loan deal.
The experience Ben Haim will take to the MLS, after spells with the likes of Bolton, Chelsea and Manchester City, will provide invaluable, according to Toronto FC president Kevin Payne.
"Tal Ben Haim has been one of the top defenders in the Premier League for nearly a decade," he told the club's official website.
"He captains his national team and Ryan thinks the world of him. He's exactly the sort of veteran defender we need."