The 1983 Japan Series was the championship series of Nippon Professional Baseball (NPB) for the 1983 season. The 34th edition of the Series, it was a best-of-seven playoff that matched the Central League champion Yomiuri Giants against the Pacific League champion Seibu Lions. For 1983 to 1985, the Pacific League had a conditional playoff system that would only occur if the first place team won the league by five games or less over the second place team, but it ended up never being used. The Lions won the series in seven games and captured their second consecutive Japan Series title.