The cosmic Marvel Comics adaptation, which focuses on a group of alien superheroes, is to be helmed by Slither and Super director James Gunn.
Deadline reports that Pratt will play the main role of Star-Lord, the leader of the Guardians who is the son of a human mother and an alien father.
The 33-year-old currently plays Andy Dwyer on the NBC sitcom Parks and Recreation, as well as having prominent supporting roles in Moneyball and Zero Dark Thirty.
The role had previously been linked to a host of actors including Zachary Levi and Jim Sturgess.
Hollywood comedy megastars Adam Sandler and Jim Carrey have also been rumoured to be competing for another role in the film.
Avengers director and writer Joss Whedon has claimed that Gunn's adaptation of the original comic books is "very twisted".
Watch the trailer for Chris Pratt's Zero Dark Thirty below: