Isabelino Gradín (8 July 1897 in – 21 December 1944) was a Uruguayan footballer and athlete.
He was one of the greatest footballers in the early era of Uruguayan football and is regarded as one of the greatest Uruguayan players before the Uruguayan win at the 1930 FIFA World Cup.
He played in the first South American Championship held in Argentina, where Uruguay became the first champions of the tournament, and finished as top scorer.
On 2 July of that tournament against Chile, where Uruguay would go on to win 4-0, Gradin and teammate Juan Delgado became the first black players in history to be fielded in an international tournament.
Gradin was also part of the Uruguayan winning team of the 1917 South American Championship.
He was also a four-time South American athletics champion in the 400 and 200 metres sprint.