Julio César Ribas Vlacovich (born 8 January 1957) is a Uruguayan association football manager and former footballer.
Ribas was appointed the manager of Primera Division Uruguaya side Peñarol in January 2009.
Following the Oman national football team's defeat against Japan in the 2010 FIFA World Cup qualifiers, the Omani Football Association sacked Ribas, due to the result and the performance of the team in that match.
He was appointed manager of Gibraltar in 2018. In February 2025, he stepped down from the position.
He is the father of footballer Sebastián Ribas who plays for Montevideo City.