Police have identified the victim as George Fawell, 24.
Two community outreach workers notified police about the body at around 10:45 p.m. after they discovered it behind the local community centre at the park, near Queen Street East and Booth Avenue. A coroner and homicide investigators were called to the scene.
Reporter Ivy Cuervo said sources have told CBC News Fawell was found with his hands tied together and his throat slashed.
Fawell's cousin Kelly Fawell told CBC News that George lived at 39 Aberdeen Avenue, which is a Toronto Community Housing unit.
She said she last saw him Thursday night at 8 p.m. He told her that he was going to visit an aunt, and was then supposed to go out with friends.
An autopsy is scheduled for Saturday.
Investigators say the area where Fawell's body was located is frequented by homeless people. It's difficult to reach, with lots of bushes and a fence to keep people out.
Police are asking anyone who may frequent the area to call them.
Anyone with information is asked to contact Det.-Sgt. Gary Giroux at 416-808-7387 or Crime Stoppers anonymously at 416-222-TIPS (8477).