Keaton wore the suit in the 1992 blockbuster "Batman Returns."
More than $4.1 million worth of cinematic treasures were sold during the event, which took place Thursday and Friday in Calabasas, Calif.
The top-selling item at the auction was a rare "King Kong" six-sheet movie poster, which went for $345,000.
A Pteranodon display with a full set of Pteranodon babies from "Jurassic Park III" sold for $97,750.
Someone paid $69,000 for John Wayne's costume from "She Wore a Yellow Ribbon," while another bidder forked over $51,750 for Julie Andrews' signature coat from "Mary Poppins" and one plunked down $43,125 for Halle Berry's Storm battle suit from "X-Men."