The 18-year-old England youth international, whose three-year Academy scholarship was due to end next summer, has signed a four-and-a-half year professional deal.
Middlesbrough-born Park, who lives in Marske, is yet to make his first team debut for Boro but was an unused substitute for the 2-2 home draw with Hull City in late November, having previously made the bench twice last season.
Manager Tony Mowbray said: Cameron is a young player with lots of potential who can hopefully make an impact at first-team level eventually.
First team coach Mark Proctor added: We are pleased with how Cameron is developing and, if he continues to work hard and perform to his potential, his progression will accelerate even more quickly.
Park is the latest Boro first team player produced by the club's acclaimed Academy.
Tony Mowbray's regular defence since his appointment as manager has comprised Academy products Jason Steele, Tony McMahon, Joe Bennett, David Wheater and Matthew Bates, while Seb Hines, Luke Williams and Richie Smallwood have all made first team appearances this season.