Kurt Magnus Atterberg (12 December 1887 – 15 February 1974) was a Swedish composer and engineer. He is best known for his symphonies, operas and ballets. He cited the Russians, Brahms and Reger as his musical influences, and his works combine their compositional styles with Swedish folk tunes.
Atterberg was born in Gothenburg. His father was Anders Johan Atterberg, engineer and brother of famous chemist Albert Atterberg. His mother, Elvira Uddman, was the daughter of a famous male opera singer.

In 1902, Atterberg began learning the cello, having been inspired by a concert by the Brussels String Quartet, featuring a performance of Beethoven's String Quartet No. 8. Six years later he became a performer in the Stockholm Concert Society, now known as the Royal Stockholm Philharmonic Orchestra, as well as publishing his first completed work, the Rhapsody for Piano and Orchestra, Op. 1. His String Quartet No. 1 in D major, Op. 2, soon followed.

While already studying electrical engineering at the Royal Institute of Technology, Atterberg also enrolled at the Royal College of Music, Stockholm in 1910 with a score of his Rhapsody and an incomplete version of his Symphony No. 1. There he studied composition and orchestration under the composer Andreas Hallén. He earned his engineering diploma a year later, as well as being awarded a State Music Fellowship. He made his conducting debut at a concert in Gothenburg in 1912, premiering his first symphony and the Concert Overture in A minor, Op. 4.

Although continuing to compose and conduct, Atterberg enjoyed a fulfilling career in several different organisations. He accepted a post at the Swedish Patent and Registration Office in 1912, going on to become a head of department in 1936, and working there until his retirement in 1968. He co-founded the Society of Swedish Composers in 1918, alongside other prominent composers such as Ture Rangström, Wilhelm Stenhammar and Hugo Alfvén. Six years later he was elected president of the society, maintaining the position until 1947. At a similar time, he became president of the Svenska Tonsättares Internationella Musikbyrå, which he also helped to found, and of which his presidency lasted until 1943. Other jobs taken on by Atterberg included his work as a music critic for the Stockholms Tidningen from 1919 to 1957, and as secretary of the Royal Swedish Academy of Music from 1940 to 1953.

Atterberg died on 15 February 1974 in Stockholm, aged 86, and was buried there in the Northern Cemetery.