Rybak was born on May 13, 1986, in Minsk, Belarus—which at that time was the Belarusian SSR in the Soviet Union. When he was 4 years old, he and his family moved to Norway. At the age of five, Rybak began to play the piano and the violin.
His parents are Natalia Rybak, a classical pianist, and Igor Rybak, a well-known classical violinist who performs alongside Pinchas Zukerman. He stated "I always liked to entertain and somehow that is my vocation".
Rybak bought a new apartment and lives now at Aker Brygge (Oslo, Norway).