Researchers provide evidence for the early cultivation and use of potato (Solanum tuberosum) at an archaeological site in the Andes Mountains of south-central Peru. Studying the domestication of the potato, an important crop in the high Andes, could help illuminate the development of highland Andean culture, but limited direct botanical evidence of potato domestication in the region has hindered research efforts. Claudia Rumold and Mark Aldenderfer* collected microbotanical samples from groundstone tools from Jisakairumoko, a site situated in the western Titicaca Basin of Peru that reflects a transition from sedentism to food production. On 14 groundstone tools, the authors found 141 starch microremains, and microscope photographs and subsequent taxonomic identification revealed that 50 of the starch granules were of Solanum origin. The potato starches were similar in size to modern potato starches, and anthropogenic wear on the starches was consistent with culinary processing methods. The findings might help us understand the development of food production in Jisakaurumoko, and more broadly, illuminate plant domestication and cultivation in the Andes Mountains.