| Pepiri-Guazu River | |
| Source1 Location: | Dionísio Cerqueira |
| Mouth Location: | Uruguay River |
| Subdivision Type1: | Countries |
| Subdivision Name1: | Argentina and Brazil |
The Pepiri-Guazu River (Spanish Río Pepirí Guazú, Portuguese Rio Peperi Guaçu) is a river of Argentina and the Santa Catarina state in southeastern Brazil. Its course forms a short portion of the international border between Argentina and Brazil. It flows from north to south into the Uruguay River.