Tatu Miettinen (born September 4, 1979) is a Finnish former professional ice hockey centre who played seventeen games in the SM-liiga for HPK and KalPa. He is the younger brother of Tommi Miettinen.
Miettinen began his career with KalPa, playing in their junior teams as well as in Suomi-sarja and Mestis, between 1994 and 2002. He joined HPK for the 2002–03 SM-liiga season and played seven games for the team, scoring two assists before returning to Kalpa. He returned to the SM-liiga with KalPa after their promotion in 2005, playing in ten games and again registering two assists.