The 26-year-old has committed his future to the Loftus Road club until the summer of 2015
"To be given the opportunity to extend my contract is fantastic for me," Mackie said.
"It's a really exciting time for the club. Now we've stayed up, I think next season could be a really big one for QPR.
"To be a part of the long-term future of the club is an aim of mine and I'm really happy."