Alf Rolfsen (28 January 1895 – 10 November 1979) was a Norwegian painter and muralist.
Rolfsen was born in Kristiania (now Oslo), Norway. He was the son of writer Nordahl Rolfsen (1848-1928) and Hedevig Martha Hastrup Birch (1858–1937). He was married to Ingrid Platou (1893–1980) in 1920. He was a cousin of both poet Nordahl Grieg (1902–1943) and publisher Harald Grieg (1894–1972). 
He studied art under Danish artist Peter Rostrup Bøyesen (1882-1952) in Copenhagen from 1913-16. He debuted in Copenhagen in 1916, followed by study in Paris from 1919-20 where he was strongly influenced by André Derain (1880–1954). After returning home, he held his first solo exhibition at Oslo in 1920. Rolfsen followed with a series of study trips to Italy during 1921-22. 
In 1922, he was given the task of painting the foundation wall in the exhibition hall at the new Telegraph Building at Kongens gate 21 in Oslo. The building was completed in 1924 based upon designs by architects Arnstein Arneberg (1882-1961) and Magnus Poulsson (1881-1958). 
In 1938, Rolfsen was given the task of decorating three of the walls in the Central Hall of the Oslo City Hall (Oslo rådhus), the site at which the annual Nobel Peace Prize ceremonies have been held since 1990. The northern wall is covered by the painting titled Arbeidets Norge fra de drivende garn til skovene i øst. On the eastern wall is the work Okkupasjonshistorien, about 30 metres (98 ft) long, with motifs from the Occupation of Norway by Nazi Germany during World War II. The painting on the western wall is titled St. Hallvard in recognition of Oslo's patron saint, Hallvard Vebjørnsson. The decorations of the City Hall were finished and uncovered in 1950.
Rolfsen is best known for his fresco paintings. His principal works include the decoration of crematorium at Vestre gravlund in Oslo from 1932–37 and the Haugesund City Hall from 1952–54. He also decorated a number of churches including Stiklestad Church in Verdal from 1929–30 and Ullensaker Church in Akershus from 1958. He is represented at the National Gallery of Norway in Oslo with several oil paintings including Kilden from 1926, Gruppe from 1931 and Den store stasjon from 1932.
Rolfsen was decorated Knight of the Swedish Order of the Polar Star in 1937 and Commander of the Royal Norwegian Order of St. Olav in 1955. He received the Prince Eugen Medal in 1951. During 1971, he received both the Arts Council Norway Honorary Award (Norsk kulturråds ærespris) and the St. Hallvard Medal (St. Hallvard-medaljen). 
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