Sinclair had a spell on loan at Plymouth last season

The 18-year-old has made two appearances for the Blues first-team this season.

Sinclair, who had a temporary spell at Plymouth last season, joins fellow Chelsea team-mates Michael Mancienne and Ben Sahar at Loftus Road.

"I'm excited to be joining QPR. I spoke to the other Chelsea boys here and they told me it's a very exciting time to be at QPR," Sinclair told QPR's website.

Sinclair, who joined Chelsea from Bristol Rovers in 2005, signed a four-year contract at Stamford Bridge in August.