| Gagamachay | |
| Elevation M: | 4400 |
| Range: | Andes |
| Location: | Peru, Ancash Region, Huánuco Region |
| Map: | Peru |
| Map Size: | 200 |
| Coordinates: | -9.3053°N -76.8661°W |
Gagamachay or Qaqa Mach'ay (Quechua qaqa rock, mach'ay cave, "rock cave", also spelled Gagamachay) is a mountain in the Andes of Peru which reaches a height of approximately 44000NaN0. It is located in the Ancash Region, Huari Province, on the border of the districts of Anra and Huacachi, and in the Huánuco Region, Huamalíes Province, Singa District.