We present a case of Visceral Leishmaniasis (VL) in a patient with gastric cancer treated with chemoradiotherapy. A 69-year-old man with gastric carcinoma had been treated with total gastrectomy, lymphadenectomy and postoperative radiotherapy with chemotherapy. Then 3 years after treatment, due to pancytopenia with progressive trombocytopenia and splenomegaly, bone marrow examination was performed and Leishmania spp. amastigotes were diagnosed. When antibiotherapy was completed, splenomegaly was eliminated and the laboratory results became normal. VL should be kept in mind in the differential diagnosis of patients, even adults, with splenomegaly, trombocytopenia and a history of contact with dogs in endemic countries such as Turkey.