| Río Blanco | |
| Mouth Location: | Río de los Patos |
| Subdivision Type1: | Country |
| Subdivision Name1: | Argentina |
The Río Blanco (Spanish for "white river") is a river of Argentina near Calingasta in the southwestern part of the province of San Juan. It is a tributary of the Río de los Patos which is one of the three sources of the San Juan River which empties into the Desaguadero River basin.