Yanarrajo, Mountain summit in Ancash Department, Peru

Yanarrajo is a mountain in the Cordillera Blanca of the Andes, about 5,055 metres high. It lies in the Ancash Region, Yungay Province, in the districts of Yanama and Yungay, within Huascarán National Park, south-west of Yanapaccha and near the Llanganuco Lakes.

Yanarrajo lies in the Cordillera Blanca within Huascarán National Park, which was established in 1975 and later named a UNESCO World Heritage Site in 1985. The mountain's Quechua-derived name, possibly meaning "black snow peak," reflects the language of the region's Indigenous communities. It stands near the Llanganuco Lakes, a long-used route across the range.

Yanarrajo lies within Huascarán National Park, and its Quechua name is commonly explained as yana (black) and rahu (snow, ice, snow-covered mountain), giving "black snow peak". The mountain stands above the Llanganuco Lakes, a pair of glacial lakes that draw walkers and climbers into the Quebrada Llanganuco.

Yanarrajo lies in Huascarán National Park, in the Yanama and Yungay districts, near the Llanganuco Lakes and south-west of Yanapaccha. Access is by foot from the Yungay side, and the park's high-altitude rules apply. At about 5,055 m, allow days for acclimatisation before climbing.

The slopes are home to specialized plants that grow close to the ground as an adaptation to fierce mountain winds. These low-growing species are remarkably well-suited to surviving the harsh alpine environment.