Many efforts in these last years have dedicated in the development of new drugs due to an increase of microbial organisms resistant to multiple antibiotics, and silver nanoparticles appears as a novel antimicrobial agent. The aim of our work was to evaluate the in vitro and in vivo antileishmanial activity of the silver nanoparticles prepared by chemical process and by biosynthesis from Fusarium oxysporum. In vitro antipromastigote activity of L. amazonensis showed that silver nanoparticles chemically synthesized (AgCHEM), biogenic silver nanoparticles (AgBIO) and amphotericin B decreased the parasite load up to 13%, 61%, and 68%, respectively. The IC₅₀ of AgCHEM and AgBIO was 103.5 ± 11.5 μM and 31.6 ± 8.2 μM respectively. The assay of antileishmanial effect of these nanoparticles was evaluated in vivo (BALB/c mice) against L. amazonensis. The mice infected with promastigotes of L. amazonensis in the ear showed that after 10 days of treatment (twice a week for four weeks) the wound in the control (mice treated with PBS solution) was large, while the wound of the mice treated with amphotericin B (positive control) exhibited low size of lesion. The same parasitemia inhibition with amphotericin B was observed when AgBIO were used at 300 fold lower concentration, and 100 fold less concentration of AgCHEM than amphotericin B. Thus, these nanoparticles can be used in wound helping like cutaneous leishmaniasis.