The properties of Annona muricata L. (guanabana) have been demonstrated in studies carried out on the its leaves, pulp, seeds, stems and fruit peel; highlighting in each of them its antioxidant properties. In the present work the quantification of the total polyphenols and the evaluation of the antioxidant capacity in the ethanolic extract of the flowers of Annona muricata L. (guanabana) was carried out. The flowers samples were collected in the province of Jaen (Cajamarca, Peru). The ethanolic extract was obtained by maceration of the pulverized dried flowers. The quantification of the polyphenols in the ethanolic extract of the flowers was carried out using the Folin-Ciocalteu technique using gallic acid as a pattern. The evaluation of the antioxidant capacity was carried out using the methods of capturing the radical’s DPPH and ABTS. + using the Trolox as a pattern for both methods....