The Alfa Romeo 177 was a Formula One car used by the Alfa Romeo team during the 1979 Formula One season, debuting at the 1979 Belgian Grand Prix. The 177 marked Alfa Romeo's return to Formula One, 28 years after winning the World Drivers' Championship titles in 1950 and 1951.

Italian motor manufacturer Alfa Romeo has participated multiple times in Formula One. The brand has competed in motor racing as both a constructor and engine supplier sporadically between 1950 and 1987, and later as a commercial partner between 2015 and 2023. The company's works drivers won the first two World Drivers' Championships in the pre-war Alfetta: Nino Farina in 1950 and Juan Manuel Fangio in 1951. Following these successes, Alfa Romeo withdrew from Formula One.