Alexander Brinchmann (15 June 1888 – 18 April 1978) was a Norwegian children's physician and songwriter, novelist, playwright and crime writer. He was a leader of the Norwegian Authors' Union from 1941 to 1945.
Brinchmann was born in Kristiania as the son of rector Jacob Ludvig Hoffmann Brinchmann and Henny Leth. He was married to Nina Grønvold from 1914 to 1924, to Johanne Ringberg from 1925, and to Gunvor Næss from 1944. He was the father of film producer and theatre director Arild Brinchmann.
Brinchmann finished his secondary education in 1906. He then studied medicine, graduating as cand.med. in 1912. From 1913 to 1914 he specialized in pediatrics in Berlin. He then worked at hospitals in Kristiania. He was authorized as a specialist in pediatrics in 1921, and became a dr.med. in 1922. Among his medical writings were articles on children's tuberculosis, and later mental hygiene for children.
Brinchmann made his literary debut in 1927 with the crime novel Mysteriet Steegener, published under the pseudonym "Roy Roberts". Among his other novels are Deilig er jorden from 1931 and Den rike mann from 1937. His comedy Karusell was staged at Nationaltheatret in 1940, directed by Gerda Ring, with Aase Bye and Per Aabel playing the main characters. Brinchmann chaired the Writers' Guild of Norway from 1938 to 1956. He chaired the Norwegian Authors' Union from 1941 to 1945, during World War II. He was a member of the Norwegian Resistance Movement's cultural council from 1943. He was arrested in January 1945 and held at Møllergata 19 and at the Grini concentration camp until 30 April 1945. He published the book Norske forfattere i krig og fred. Den Norske forfatterforening 1940–1968 in 1968, in cooperation with Sigurd Evensmo.