Krajna was born in 1966 in Zagreb, Croatia. He began his accordion studies
in Zagreb and continued at the famous Kraguevac Music School with Prof.
After, Marian continued his accordion studies in Moscow at the Russian National Music Academy "Gnessin" with Prof. Vlachislav Semionov where he graduated in 1990.
In Moscow, in parallel with his accordion degree, he studied for 5 years conducting symphony orchestra with Professor Kozhuhar and also graduated that course in 1990.
Marian successfully competed internationally and was the LAUREATE of the 1985 Confédération Mondiale de L'Accordéon - CMA - Trophée Mondial de l'Accordéon in Portugal.
Marian has an active musical and accordion career. He has collaborated and performed with many symphony orchestras, conductors and composers in Croatia and internationally.
His accordion students are winning many prestigious international accordion competitions.
Marian is a Director of the "Croation Academic Accordion Orchestra" in Zagreb which has performed extensively in Croatia and toured to Italy, achieving 2nd place at the Trieste Fisarmonae International Competitions in 2006.
Marian is the Principal of the Zlatka Balokovica, Zagreb (government High School of Music) since 1997.
Marian is often invited to hold accordion master classes and seminars in Croatia and internationally.