Oscar Alfredo Ruggeri (born 26 January 1962 in Corral de Bustos, Córdoba) is a former footballer. Nicknamed "El Cabezón" ("The Big-Headed One"), Ruggeri is one of the most successful defenders ever to come out of Argentina.

Ruggeri started his career at Boca Juniors, playing with Diego Maradona, with whom he won a league title in 1981. In 1985 he moved to rivals River Plate, where he won the Libertadores Cup, the Intercontinental Cup and another league title in 1986. In 1988 he left for Europe where he played for Spanish clubs Logroñes and Real Madrid, where he won yet another league championship. He also played for Vélez Sársfield, Ancona in Italy, América in Mexico, San Lorenzo and Lanús, where he ended his career.

During his career he represented his country in three World Cups, captaining Argentina in the final two games of the 1994 competition, after Diego Maradona was expelled from the tournament. Ruggeri was also a key piece in the Argentina teams that won the trophy in 1986 and lost the final to West-Germany in 1990. After losing to Romania in the 1994 tournament, Ruggeri retired from international football having played 97 international games, an Argentine record until it was surpassed by Diego Simeone.

Ruggeri played in 21 Copa América games, a national record he shares with José Salomón.