Piotr Rubik (born 3rd September 1968 in Warsaw) is a Polish composer of music for orchestra, films and theatre.

He learned to play the cello from the age of 7, went on to a musical secondary school, and then studied at the Frederic Chopin Academy of Music in Warsaw. Later he became a member of the world-class orchestra Jeunesses Musicales. He studied film score composition in Siena, Italy, under Ennio Morricone.

His magnum opus to date is the oratorio Tu Es Petrus, Latin for You Are Peter, which he dedicated to Pope John Paul II. It forms only one part of his Tryptyk Świętokrzyski (Holy Cross Triptych) which he co-wrote with Zbigniew Książek. The other parts are Oratorium Świętokrzyska Golgota (Holy Cross of Golgotha) and Oratorium Psałterz Wrześniowy (September Psalter) with Tu Es Petrus forming the second part.