Otto Kemppainen (born 27 October 2003) is a Finnish professional footballer who plays as a defender for Veikkausliiga club AC Oulu and the Finland U21 national team.

[1] Born in Rovaniemi, Kemppainen started his playing career in Rovaniemen Palloseura (RoPS).

After a short stint in Hellas Verona academy in 2022,[2][3][4] Kemppainen signed a professional contract with Veikkausliiga club SJK Seinäjoki on 26 July 2022, on a deal until the end of 2024.

[5] On 4 November 2024, Kemppainen signed with AC Oulu in Veikkausliiga on a two-year deal with a one-year option.

[6]