Katja Kolehmainen (née Korkeala) entered the Espoo Music Institute at the age of eight. Three years later she enrolled in the Sibelius Academy’s youth department, and continued as a student of Arto Noras, Erkki Rautio, and Heikki Rautasalo. In 1989-1990 she studied at the Academy of Music in Kraków as a student of Professor Witold Herman. In 1984 Kolehmainen shared the first prize at the Espoo Chamber Music Competition and in 1986 she was one of the finalists at the Turku Cello Competition.
Kolehmainen worked as solo cellist at the City Orchestra of Kouvola between 1990 and 1992 and at the Turku Philharmonic Orchestra since 1993, as sub-principal since 2011. In addition, Kolehmainen performs actively as a soloist and chamber musician in various events in Finland and abroad.