Cases of visceral leishmaniasis (VL) in the course of human immunodeficiency virus (HIV) infection have regularly been recorded, mainly in southern Europe. HIV infection can increase the risk of VL development by 10–100 times in endemic areas. We describe the occurrence of this co-infection in 15 patients from Brazil. The mean age of the patients was 38 ± 8.8 yr, with 86.6% males. The mean time between HIV diagnosis and the onset of visceral leishmaniasis was 44 ± 39 mo. The main signs and symptoms presented at admission were splenomegaly (73%), weight loss (73%), cough (67%), fever (67%), asthenia (60%), and diarrhea (60%). The mean T CD4+ lymphocyte count was 173.7 ± 225.6 cells/mm3, and viral load was 51,030 ± 133,737/mm3. Treatment consisted of pentavalent antimonials (67% of cases). Most (87%) patients recovered from VL infection; death occurred in 1 patient due to septic shock. VL is an important opportunistic infection in HIV patients, which is potentially fatal, even when correct treatment is completed. Treatment should be done with pentavalent antimonials or amphotericin B in the case of relapse. Although there is no consensus, secondary prophylaxis should be considered in severe cases.