Marian Peter Opala (January 20, 1921 – October 11, 2010) was a Polish-American lawyer and jurist who served as a justice of the Oklahoma Supreme Court from 1978 to 2010. Opala was appointed to the state's highest court in 1978 by Governor David Boren. Prior to his appointment as a Supreme Court Justice, Opala served the State of Oklahoma in various positions, including Assistant County Attorney for Oklahoma County, Administrative Director of the Oklahoma State Court System, and as a judge on the Oklahoma Workers' Compensation Court.