Mike Barnes is a fictional character from the movie The Karate Kid Part III. He is played by Sean Kanan.

Mike Barnes is first noticed by Terry Silver whilst the latter is sitting in the back of his Rolls-Royce limousine, smoking a cigar and reading a karate magazine. Silver takes note of a full-page ad proclaiming Barnes to be "Karate's Badboy" and featuring a very menacing photo of Barnes's screaming face. He says, "perfect," and thus the wheels are set in motion for what is to be the primary plot line of Karate Kid Part III - the attempt to humiliate Daniel after forcing him to compete in the tournament.

Barnes is a handsome young man with an exceptionally built physique, stylish wardrobe, and spiked blonde hair which was notably before its time in 1989. He is sadistic, extremely confident, cunning, and a shrewd negotiator (revealed in the scene in which he demands 50% ownership of the Cobra Kai dojo franchise and manages to get it.)