Heikki Veli Uolevi Sarmanto (born 22 June 1939) is a Finnish jazz pianist and composer.

Sarmanto was born in Helsinki, Finland, and began to play jazz during the 1960s. He studied first at the Sibelius Academy and later at the Berklee College of Music in Boston between 1968 and 1971. In 1970 he was chosen as 'Jazz Musician of the Year' in Finland and, the following year, he won top prizes at the Montreux Jazz Festival in both piano and combo categories.

Sarmanto has released around 40 recordings, numerous published scores, and songbooks, as well as having several film scores to his credit. He has collaborated with jazz musicians such as Sonny Rollins, Art Farmer, Helen Merrill, George Russell and Jeannine Otis; in addition to his work in the classical arena with baritone Jorma Hynninen, the Finnish Radio Symphony Orchestra and the Tapiola Children's Choir.

In September 1998, Sarmanto was appointed Artistic Director of the UMO Jazz Orchestra.

Pekka Sarmanto, who is also a jazz musician, is Sarmanto's brother.