The authors analysed the results of Montenegro Test in 402 patients with mucocutaneous leishmaniasis from Espírito Santo State, where the Leishmania braziliensis braziliensis has been isolated from humans cases and dogs. The test was positive in 371 cases (92.2%) before treatment. The Montenegro Test given during or after treatment changed the results in 17 of 20 negative cases. The remaining 3 cases and 9 which changed the results had positives biopsies. It was demonstrated again the efficiency of the Montenegro Test in the diagnosis of mucocutaneous leishmaniasis.