| Baztan | |
| Name Other: | Baztán |
| Subdivision Type1: | Country |
| Subdivision Name1: | Spain |
| Subdivision Type3: | Region |
| Subdivision Name3: | Navarre |
| Source1: | Izpegi & Iztauz |
| Source1 Location: | Erratzu, Spain |
| Mouth: | Bidasoa |
| Mouth Location: | Oronoz-Mugairi |
| Mouth Coordinates: | 43.1378°N -1.6121°W |
The Baztan (Basque: Baztan, Spanish; Castilian: Baztán) is a river in northern Spain. It is the main, right headwater of the river Bidasoa. Downstream from the confluence with the river Marin at Oronoz-Mugairi, it is called Bidasoa.