Roar Berthelsen (3 November 1934 – 1 August 1990) was a Norwegian long jumper. He represented Mandal og Halse IL and IK Tjalve.

At the 1954 European Championships he finished eleventh in the long jump final with a jump of 7.16 metres. He also competed at the 1960 Summer Olympics without qualifying for the final.[1] He became Norwegian champion in long jump in 1954, 1956, 1957 and 1959.