Leishmaniasis is an important parasitic disease in Turkey and the world. Anti-leishmanial drugs such as sodium stibogluconate, miltefosine, paramomycin, amphotericin B, and pentamidine are used for the treatment of leishmaniasis. However, the drugs, used for the chemotheraphy of leishmaniasis, have some side effects such as nephrotoxicity, hepatotoxicity, and teratogenicity. In addition, it is deemed that the discovery and development of the new therapeutic agents must be given priority due to the development of resistance against antimony compounds. The purpose of this study is detecting the anti-leishmanial activity of ten different synthesized hydrazone compounds against Leishmania infantum promastigotes via the microdilution method. The prepared hydrazone compounds, having the concentration of 6 mu g/ml, were added to RPMI-1640 media and the dilution of the hydrazone derivates was performed in the wells of microplates in the range of concentrations of 3 - 0.003 mu g/ml. The microdilution broth method in the microplates was prepared, than the adjusted standard Leishmania infantum promastigotes, 2.5x10(7)cells/mL, were added, into the mentioned microplates which was incubated in 27 degrees C. Twenty h later, the alamar blue were added on the microplates and they were incubated for 4 h. The proliferation of promastigotes was evaluated in 24, 48, and 72 h. It was considered that changing the color from blue to pink in the wells were exhibiting the growth of parasites, while the unchanged color was not. The present study has revealed that the most effective substances against Leishmania infantum promastigotes were 5e, 5g, and 5h compounds (MIC 0.187 mu g/ml) while the least effective compound was 5i (MIC 3 mu g/ml). There is a need for further studies on in vitro activity against the Leishmania amastigotes in macrophages cultures and in vivo experimental animal models for the synthesized compounds showing anti-leishmanial effect in the present study.