A new species of Styrax L. from the region of Cusco, Peru, is described and illustrated. Styrax excelsus P. W. Fritsch belongs to Styrax subser. Foveolaria (Ruiz & Pav.) P. W. Fritsch through its flowers shorter than or up to 10 mm; number of stamens equal to the number of petals (five); near-basal placentation; three ellipsoid ovules per flower (i.e., one per carpel); and presence of only female flowers, which suggests a gynodioecious breeding system. It is similar to S. maninul B. Walln. but differs by its taller habit; abaxial surface of the leaf blade with ferruginous, stellate trichomes that are generally smaller but with more arms and prominent reticulate tertiary veins; acute or slightly acuminate leaf apex; shorter inflorescences with fewer flowers; a longer corolla; and narrower staminodial pseudoanthers. The new species is only known from the type.