Crude extracts from barks of Stryphnodendron adstringens and Caryocar brasiliensis, native species of Cerrado, have been screened at 400 ppm for antiparasitic activity against Trypanosoma cruzi. Mice were inoculated with 1x104 parasites, after 24 h they were treated with one day dose extracts during ten days. The trypanosomicidal activity was evaluated each 48 h until animals death. The extracts of S. adstringens and C. brasiliensis decreased significantly the number of parasites in the blood.