Carlos Alberto Sainz (born 13 December 1937) is a former Argentine association football player. Sainz began his career in 1958 at Argentinos Juniors, where he played until 1961. In 1962 he moved to Club Atlético River Plate with whom he reached the final of the 1966 Copa Libertadores, where they lost to Uruguayan side C.A. Peñarol. He stayed at River Plate until 1967 and then moved to San Lorenzo from Mar de Plata in 1968 before retiring in 1969.