Seiko Hashimoto (橋本 聖子, married name: Seiko Ishizaki (石崎 聖子), born October 5, 1964 in Hayakita, Hokkaido) is a Japanese politician who was formerly a speed skater and track cycling sprinter. She has the most Olympic appearances of any Japanese athlete, representing her native country in four consecutive Winter Olympics from 1984 to 1992 and in three consecutive Summer Olympics from 1988 to 1996. She is currently a member of the House of Councillors from the Liberal Democratic Party, and serves as the President of the Japan Skating Federation.