The diagnosis of visceral leishmaniasis (VL) in patients with fever and large spleen relies on the detection of Leishmania parasites in tissue samples and on serological tests. Parasitological techniques are invasive, require sophisticated laboratories, are time-consuming or lack precision. Recently, rapid and easy to perform diagnostic tests have become available. This study aims to discuss the epidemiological profile of visceral leishmaniasis in the region of Marrakech and to highlight the importance of biological diagnosis in the identification of the disease, by comparing the contribution of RDT with the usual tests.