The 21 year-old has just finished a loan stint at tomorrows opponents Crewe Alexandra, scoring 3 times in 6 appearances.
The loan agreement has the option for Hitchcock to extend his deal until the end of the season if the initial spell is successful.
Steve Evans told themillers.co.uk: "We’ve always liked him and watched him playing in games, both behind closed doors and reserve games for QPR. I spoke to Harry Redknapp about him a while ago and although things didn’t work out at that time, we tracked him when he went to Crewe. He’s done well there, got a goal every two games in this division and was unlucky not to get more actually.
"He’s a young man whose movement is good, he’s very creative and he’ll get a goal and it’s a bit like Nouha Dicko where he’s been hiding away in the reserves, so hopefully he can have a big effect and we’ll build a good relationship together.”