Ota Koji (born January 23, 1952 in Misawa, Aomori, Japan) is a Japanese former professional baseball pitcher in Japan's Nippon Professional Baseball, and belongs to Mainichi Broadcasting System, Inc. as a commentator in baseball live on radio and TV.
He is known for pitching in the final of 1969 National High School Baseball Championship. He pitched 18 shut-out innings for Misawa High School on one of the most-watched TV programs in Japanese history. After the game was called due to darkness, he returned the next game, but lost 4-2. Before he graduated from high school, a book had been written about him and several TV documentaries had been aired. A popular figure among women due to his appearance, this handsome young boy became an instant celebrity nationwide. The game was the best game in Japanese baseball history.