Matthew Cvetic (March 4, 1909 – July 26, 1962) was a Pittsburgh native who was a spy and informant working for the Federal Bureau of Investigation inside the Communist Party of the United States (CPUSA) during the 1940s. He told his story in a series in the Saturday Evening Post, and his experiences were then fictionalized in the old time radio show I Was a Communist for the FBI, adapted for a Warner Brothers motion picture in 1951. He testified before the House Un-American Activities Committee in the 1950s.