Judo at the 1964 Summer Olympics – Men's open category

The open category was a judo event held as part of the Judo at the 1964 Summer Olympics programme. The weight class allowed judokas of any weight. The competition was held on Friday, October 23, 1964.

Nine judokas from nine nations competed. The final is featured in the Kon Ichikawa film, Tokyo Olympiad.

Elimination round
he nine competitors were split into three pools of three. Each pool held a round-robin tournament, with the top competitor from each pool advancing to the semifinals. The second-place judoka from each pool progressed to a relegation pool, where they played another round-robin. The winner of this pool then secured the fourth spot in the semifinals.

Pool A

Pool B

Pool C

Repechage
Campbell's injury, sustained during his match with Glahn, forced him to retire. Ong took his place in the repechage group. Kaminaga defeated both other judokas to move on to the semifinals.

Repechage pool

Knockout rounds
The remaining four judokas competed in a single elimination bracket. Both losers in the semifinals won bronze medals. Kaminaga, who had advanced through the repechage, defeated Glahn to earn a rematch against Geesink. Geesink, who had defeated the Japanese judoka in the first round, did so again in the final match.

Noted participants
Campbell would go on to serve in the United States Senate.