The plant Solanum tuberosum is used in Colombian folk medicine for the treatment of hypertension. We evaluated the antiaggregant properties on human platelets of an ethanolic extract (96%) obtained from the skin of tubers of this species. Extracts from two varieties, sabanera and pastusa revealed in vitro dose-dependent (10–100 mg/mL) antiaggregant effects on platelets stimulated with adenosindiphosphate (ADP 10 μ M), epinephrine (300 μ M), collagen (10 μ g/mL), and arachidonic acid (150 μ g/mL). The IC50 values for the sabanera and pastusa varieties were, respectively, 1,8 μ g/mL and 0,4 mg/mL, against ADP; 4,4 μ g/mL and 0,1 mg/mL against epinephrine; 34,1 μ g/mL and 1,3 mg/mL against collagen, and 12,3 μ g/mL and μ g/mL, against arachidonic acid, a key precursor in prostaglandin synthesis. Our findings suggest that S. tuberosum has a promising pharmacological profile since it combines the hypotensive effects, previously described, with the antiaggregant ones; therefore, it is potentially useful for the treatment of cardiovascular disorders such as hypertension and coronary artery disease.