Watson has impressed the Rangers boss since moving to Loftus Road on a loan deal that is due to expire at the end of this month.
"I'd like to keep Ben at the club," Magilton told BBC Sport
"If we can keep him until the end of the season or do a deal to sign him then I'd be delighted.
"It's something we'll leave to the money men. I definitely want him.
"He's a player I rate highly. He is energetic, keen and ambitious."