Ubaldo Néstor Sacco (Buenos Aires, 28 July 1955 – Mar del Plata, 28 May 1997) was an Argentine boxer who was the Junior Welterweight champion of the world.
Known as "Uby", Sacco turned pro in 1978 and won the World Boxing Association light welterweight title by TKO over Gene Hatcher in 1985. He lost the belt the following year to Patrizio Oliva by decision.
Sacco died in Mar del Plata, Argentina of meningitis in 1997.