The lawsuit, filed Tuesday in Los Angeles Superior Court, also names the producers of the awards show, the Fox Reality Channel.
Fairplay, whose real name is Jon Dalton, was presenting an award on stage at the Fox Reality Channel "Really Awards" on Oct. 2 when Bonaduce unexpectedly approached him on stage.
When Fairplay ran and jumped into his arms, Bonaduce tossed him over his shoulder. Fairplay hit the floor head first and was hospitalized for injuries to his face and mouth.
With Fairplay "on the ground and blood and broken teeth on the stage floor, Mr. Bonaduce proceeded to parade around the stage with pride," according to the lawsuit.
A video of the incident captured the sound of the audience booing.
Fairplay, 33, is suing for unspecified damages to cover medical expenses, emotional distress and lost earnings. He is also seeking punitive damages.
After an investigation, the district attorney's office decided not to press charges against Bonaduce.
Bonaduce did not intentionally injure Fairplay and his "actions fell within the realm of self-defense," Deputy District Attorney Jeffrey Boxer wrote last week.
Fairplay appeared in the 2003 CBS show "Survivor: Pearl Islands" and came in third.
Bonaduce, 48, was a child star on "The Partridge Family." He starred in the 2005 reality show "Breaking Bonaduce," and has recently co-hosted Adam Carolla's radio show.
By Raquel Maria Dillon