John Adam Belushi (pronounced /bəˈluːʃi/; January 24, 1949 – March 5, 1982) was an American comedian, actor, and musician best known as one of the original cast members of the NBC sketch comedy show Saturday Night Live and for his roles in the films National Lampoon's Animal House and The Blues Brothers. He was the older brother of Jim Belushi.

Belushi was born in Chicago, Illinois, the son of Agnes Belushi (née Samaras), a first generation Albanian-American, and Adam Belushi (1918–1996), an Albanian immigrant and restaurant operator who left his native village, Qytezë, in 1934 at the age of sixteen. The family's name at the time of immigration was Bellios, or Belliors. Belushi was raised in the Albanian Orthodox church and grew up outside Chicago in Wheaton with his sister Marian, and two brothers, Jim, five-and-a-half years his junior and Billy. He attended Wheaton Central High School, where he met his future wife, Judy Jacklin.

Belushi's first big break as a comedian occurred in 1971, when he joined The Second City comedy troupe in Chicago. He was cast in National Lampoon's Lemmings, a parody of Woodstock, which played Off-Broadway in 1972 and showcased future Saturday Night Live (SNL) performers Chevy Chase and Christopher Guest.