| Jayaq Mayu | |
| Name Etymology: | Quechua |
| Subdivision Type1: | Country |
| Subdivision Name1: | Bolivia |
| Subdivision Type3: | Region |
| Subdivision Name3: | Potosí Department |
| Source1: | Cerro Rico |
| Source1 Location: | Potosí Municipality |
| Mouth: | Agua Dulce River |
| Mouth Location: | Yocalla Municipality |
Jayaq Mayu (Quechua jaya pungency, locoto, mayu river, -q a suffix, "spicy river", hispanicized spelling Jayac Mayu)[1] is a Bolivian river in the Potosí Department, Tomás Frías Province, in the south of Potosí. It originates on the west side of the mountain Cerro Rico or P'utuqsi Urqu located in the Potosí Municipality. Then it flows in a north west direction until meeting Agua Dulce River in the Yocalla Municipality. This river shortly afterwards forms the Tarapaya River at its confluence with Ribera de la Vera Cruz. Jayaq Mayu belongs to the Pillku Mayu drainage basin.