However, after the start of World War II, he traveled with his mother across Poland to Bydgoszcz, where the composer's father was hiding from the Nazis.
In 1952, Stachowski began attending the piano classes given by Stanisław Czerny at the State First Level Music School in Kraków.
During his studies at the State Higher School of Music in Kraków (today known as Academy of Music in Kraków) he achieved his first international successes: in 1968, the prize during the International Competition of the 'Gaudeamus' Foundation for the piece entitled Musica Con una Batuta del Tam-tam; the first prize during the Artur Malawski Competition for Composers for the piece Neusis I as well as the award for Sequenze Concerttatii received during the Competition for Young Musicians organised by the Polish Composers’ Union.
The following year, he won second prize in the International Competition organised by the 'Solidarity Committee' in Skopje for his piece entitled Chant de l'espoir.
In 1970 Audition for flute, cello and piano was Marek Stachowski's first piece which was performed during the Warsaw Autumn festival.