He is a graduate of the Academy of Music in Wrocław in Professor Grzegorz Kurzyński's piano class and Professor Mieczysław Gawroński's conducting class. He collaborates with Wrocław composers such as Agata Zubel, Sławomir Kupczak and Robert Kurdybacha, performing their piano and orchestral compositions. As a conductor, he collaborates with the Symphony Orchestra of the Karol Lipiński Academy of Music in Wrocław and, since 2008, has led the Symphony Orchestra of the Karol Szymanowski Academy of Music 1st and 2nd degree in Wrocław. In 2018, he prepared and conducted a series of performances of Karol Szymanowski's operetta "Lottery for Husbands, or Fiancé No. 69", which was the graduation performance of the students of the Vocal Department of the Academy of Music in Wrocław.

For 10 years he was a pianist in Prof. Danuta Paziuk-Zipser's singing class. He took part as a pianist in international vocal courses in Duszniki-Zdrój. Marcin Grabosz also arranges works from the classical and jazz music canon. He has been touring extensively as a chamber music pianist for several years. He has performed as a pianist in Russia, Austria, Slovakia, the Netherlands and Germany, among others. He has to his credit many world premieres of works by composers from Wrocław.

He won a special prize for the best pianist-accompanist at the 20th and 21st Century Music Competition in Radziejowice, organised by the Polish Contemporary Music Society. In 2009, for the Cd Accord label, together with Agata Zubel, he recorded an album of song cycles by Alban Berg, Aaron Copland and Paweł Szymański. He also works at the Stanisław Wyspiański Academy of Theatre Arts in Wrocław, where he is involved in interpreting the songs performed by students.

He holds a doctorate of musical arts in the artistic discipline of instrumental music. He has also been composing for several years. His chamber works have been performed, among others, at national and international cello competitions.