Winger Kadeem Harris, midfielders Josh Scowen and Jesse Kewley-Graham and defender Anthony Stewart will link up with Gary Waddock's first-team squad over the summer.
Head of youth Richard Dobson told the club's official website: "Each of the boys has shown in youth and reserve-team games and when training with the first team that they deserve a professional contract.
"I'm pleased that their hard work has earned them this reward but it's important that they carry on working hard."
Waddock said: "I'm looking forward to welcoming them into the first-team squad and they have the potential to become very exciting players for the club."
Source: PA
Source: PA