He was born in Piraeus in 1931. He studied music at the Piraeus and Hellenic conservatories. He received his first dance lessons from Aggelos Grimanis and Leonidas Vakoulis. He was initially hired by the Greek National Opera (GNO), where he choreographed and danced in operas, operettas and in the ballet The Death of the Valiant Woman [O thanatos tis andreiomenis] by Manolis Kalomiris (1950-1954). At the same time, he was closely associated with the Greek Ballet of Rallou Manou (1950-1952). He then traveled to Paris where he studied alongside Preobrazhenska and Egorova, and joined the ballets of Rolan Petit (1954) and Marquis de Cuevas (1956-1958). He traveled around the world (1956-1958) as dancer and choreographer with England’s Ballet Rambert. He then went to New York for further study under George Balanchine, Valentina Periozlaveck and Martha Ghaham (1961-1962). In between, he participated in productions of the GNO (1958-1963) and of the Athens Festival (1955, 1959). After settling permanently in Greece he was hired again by the GNO (1963). Together with others he founded the Yannis Metsis Dance Group in 1965 which was renamed into Athens Experimental Ballet in 1973. This group gave performances around Greece and abroad (Cyprus, Romania, Europe), and introduced and promoted the expressive dance and the neoclassical ballet in Greece (1965-1990). Metsis created tens of modern ballets in music by Greek and foreign composers, and collaborated with Greek and foreign choreographers (Dora Tsatsou, Haris Mantafounis, Leonidas de Pian, William Carter, John Cranco, John Neumaier e.a.) All the while he collaborated regularly with GNO, choreographing operas, operettas, musicals and ballets (1963-1996). He served as an advisor to the board of management of GNO since 1970. He taught at the State School of Orchestral Art, and at the ballet schools of Vakoulis, Matey and Manou. He also served as chairman of various committees (Ministry of Culture, Foundation of State Scholarships e.a.) and was honored with special awards.