Abstract. The World Health Organization considers leishmaniasis as one of the six most important tropical diseases in the world. Actually, it is endemic in 88 countries and the different types of this disease affects approximately 12 million of people worldwide. Leishmaniasis is caused by protozoan parasites of the genus Leishmania. The mechanisms of the cellular response against leishmaniasis are not completely known. Additionally, there is still a lack of understanding on the metabolism of the parasite. In this way, we have developed and analyzed a computational model for the immune response to Leishmania major infection by using multi-agent systems. In our model, we have seven different cell types: Leishmania major, CD4-T cell (resting and activated), macrophage (resting, activated, infected, chronically infected), eosinophil (resting and activated), neutrophil, dendritic cell (resting and activated), and keratinocyte. Furthermore, there are void sites to simulate the mobility of the cells. Our model can simulate migration, activation, phagocytosis, and cellular death by lifetime. It was constructed on a three-dimensional cubic lattice. The results show that the kinetics of different cell types does not change for different lattice size. Furthermore, our results suggest that an agent-based approach is a suitable instrument for investigating the cellular interaction. Keywords.multi-agent, leishmaniasis, computational model, immune response, protozoan infection 1 vivgalvao@gmail.com 2