Manilkara subsericea (Mart.) Dubard (Sapotaceae) is popularly known in Brazil as "guracica". The species from the genus Manilkara have been studied and several substances were found, including triterpenes. In the present study, we describe the anticholinesterasic activity of an extract of M. subsericea containg beta-amyrin acetate (76.3 %) and alpha-amyrin acetate (23.7 %) using a TLC bioassay.