| São João River | |
| Pushpin Map: | Brazil |
| Pushpin Map Size: | 300 |
| Pushpin Map Caption: | Location of the mouth in Brazil |
| Pushpin Map Alt: | Map showing the location of the river mouth in Brazil |
| Source1 Location: | Paraná state |
| Subdivision Type1: | Country |
| Subdivision Name1: | Brazil |
| Mouth: | Paraná River |
| Mouth Coordinates: | -23.8147°N -54.0042°W |
The São João River is a tributary of the Paraná River in Paraná state, southern Brazil.