Not to be confused with the MLB Japan All-Star Series

The Japan Championship Series(日本選手権シリーズ,Nippon Senshuken Shiriizu), or Japan Series(日本シリーズ,Nippon Shiriizu) is the annual championship series in Nippon Professional Baseball and the top baseball league in Japan. It is a seven-game series between the winning clubs of the league's two circuits, the Central League and the Pacific League. The Series is the highest level of play in professional baseball in Japan. It is usually played in October or November. As in all of the best-of-seven series, the first team to win four games is the overall winner and is declared the Japan Series Champion(日本一,Nippon Ichi, number one in Japan) each year. The winner of the Japan Series also goes on to be the Japanese representative team in the annual Asia Series.