During my ongoing study of the systematics of the Peruvian wild tuberbearing Solanums I have reviewed some rare and interesting collections made in the past which previously had seemed very difficult to classify correctly. After reviewing and comparing some of these specimens with other collections gathered in the main herbaria of U.S.A. and Europe, I am convinced of the existence of some still undescribed species such as the one I am presenting here under the name ofSolanum sawyeri in honor of Dr. Richard Leander Sawyer, promoter and founder of The International Potato Center located at Lima, Peru. Solanum sawyeri, is acclimated to the warm humid tropics of Southern Peru. It grows in forests of the low land regions of the Eastern province of Urubamba in the Department of Cusco and thereafter might serve as a source of breeding material for those who want to select potato cultivars for the low land tropics. This species belongs to the series Tuberosa with 2n = 2× = 24 chromosomes.