The 22-year-old arrives at the newly promoted Premier League outfit on a four-year deal after bringing an end to his two-year stint in south Wales.
The deal will be subject to international clearance, but Mutch revealed his excitement at getting started in his new surroundings.
"I don't see a better place for me than QPR at the moment," he told the club's website. "The club is heading in the right direction and I'm really excited about the season ahead.
"I thought I had a good first season in the Premier League last year with Cardiff, so I was delighted when QPR came in for me and offered a route back to the top flight.
"I'm really happy to be here and hopefully we can do well this season."
Mutch scored seven goals in 35 Premier League appearances for Cardiff last term, and QPR manager Harry Redknapp is hopeful the new signing can make a similar contribution at Loftus Road.
"Jordon's a fine young player, with a big, big future," he said. "He's already shown what he can do at this level with Cardiff last season with a decent goals return – and this move will provide him with a great platform to take his game on to the next level.
"He wants to learn and improve his game. He's a good pro with a great attitude and this is a big opportunity for him at QPR."
Mutch becomes the second Cardiff player to move to west London during the close-season, after Steven Caulker made the same switch last month.
