The Premier League's bottom club beat off competition from Newcastle to land the 26-year-old, who has agreed a four and a half year contract.
Remy began his career with Lyon before moving on to Nice and then Marseille, for whom he scored 27 goals in 68 appearances.
He has been capped 17 times by France, scoring four goals, and he will be eligible to make his R's debut at West Ham on Saturday, subject to receiving official clearance.
QPR manager Harry Redknapp said: "I'm delighted to bring him in - he's a great buy for us.
"I didn't think we'd get him to be honest but (chairman) 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.
"He's quick, can score goals, and makes great runs. His movement is excellent. He's got the potential to be a really outstanding striker."
Remy said: "Harry played a big part in me coming here. 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.
"After seven years in France, this is the right time for me to pursue a new challenge in the Premier League - the best league in the world.
"I am confident I can adapt to the Premier League. My main characteristics have taken me to the level I am at today, but I am keen to keep improving."