The France international will wear the No. 18 shirt at Loftus Road and is eligible to make his Hoops debut against West Ham on Saturday, subject to receiving international clearance.
“I’m delighted to bring him in – he’s a great buy for us," manager Harry Redknapp told the club's official website.
“I didn’t think we’d get him to be honest but Tony Fernandes worked ever so hard on this. He wouldn’t give up on it, and it’s great that we now have him here with us.
“He’s always been a player I’ve admired. I’ve watched him on so many occasions throughout the last few years. I actually spent three or four hours with him last year so he knew what I thought of him, and I think that was important."
Remy had looked set to join Newcastle United but has opted for west London instead, with the former Nice man hailing Redknapp as being key to his decision.
"Harry played a big part in me coming here," the striker told QPR's website. "I spoke to him and Tony Fernandes at length and they made it clear they wanted me here. They gave me the right motivation to join QPR.
“I want to develop my game here. This season the objective is to stay up but beyond that we have greater objectives."