Trypanosoma cruzi, the ethiologic agent of Chagas disease, is transmitted through triatomine vectors during their blood-meal on vertebrate host. These hematophagous insects usually ingest in a single meal about 10 mM heme bound to hemoglobin and the first transformation of T. cruzi trypomastigotes into epimastigotes occurs in the crop and initiates few hours after parasite ingestion. One important intracellular mechanism to control heme homeostasis in several organisms is its enzymatic degradation by heme oxygenase (HO). HO catalyzes the oxygen-dependent degradation of heme to biliverdin (Bv), carbon monoxide (CO) and iron (Fe⁺²). HO has been extensively studied in the last few years in different models, also due to the biological activity of its products. We have investigated the role of heme at cell proliferation. T. cruzi epimastigotes Dm28c strain, at the exponentional phase and observed that the addition of heme increased significatively the parasite proliferation in a dose-dependent manner. In order to investigate a possible contribution of heme and its products we evaluated the effect of cobaltic protoporphyrin IX (CoPP, a HO inducer), Sn protoporphyrin IX (SnPP, a HO inhibitor), and Bv, a product of heme degradation. The addition of SnPP decreased significatively the parasite proliferation in a dose-dependent manner, also decreasing T. cruzi growth in the presence of heme. Nevertheless, when Bv was added to the culture this effect was reversed, leading to an increase of proliferation. CoPP did not interfered on epimastigotes growth in the absence or in the presence of 30µM of heme. To investigate whether the proliferative effect of heme was determinated by a protein kinases (PK) mediated signaling pathway, we next evaluated the effect of several PK inhibitors. The parasites were incubated in the absence or in presence of 30µM heme and in the absence or presence of PK inhibitors. Among all inhibitors tested, only KN93 (2µM), a classical inhibitor of CaM kinases, had a signifficative effect at cell proliferation mediated by heme. In order to test the specificity of KN-93 effects, we used KN-92, an inactive analog of KN-93 and no effect on epimastigotes proliferation was observed. In conclusion, our results shows that heme increases epimastigotes proliferation, biliverdin is so important to T. cruzi proliferation than heme and CaM kinase pathway is involved on the signaling mediated by heme.