The 2003 Nippon Professional Baseball season was the 54th season of operation for Nippon Professional Baseball (NPB). This was the last season in which both leagues had their champion automatically go to the Japan Series, as the Pacific League would institute a playoff in 2004. This was the last season for the Nippon-Ham Fighters at the Tokyo Dome (which also housed the Yomiuri Giants), who elected to move to the Sapporo Dome in Kitahiroshima, Hokkaidà  in the Sapporo metropolitan area. Hanshin clinched their first league pennant in eighteen years with their victory on 14 September. The season ended with the Fukuoka Daiei Hawks defeating the Hanshin Tigers in the 2003 Japan Series in seven games in a historic matchup that saw the home team win all seven games for the first time ever to go along with three games ending on walk-off hits.