The French international has previously been linked with a host of Premier League clubs, including Tottenham Hotspur and Newcastle United. Until now though, the French international had always remained loyal to Marseille.
"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," he told the club's official website.
"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 in the Premier League."
Remy will wear the number 18 shirt at Loftus Road.