A 26-month-old male mixed-breed dog of Korean origin was subjected to necropsy following death after a history of decreased appetite and weight loss. Necropsy revealed generalized lymphadenopathy and splenomegaly. Histopathological examination of samples from the spleen, mandibular lymph nodes, liver, kidney, and large intestine showed granulomas with numerous macrophages containing intracytoplasmic Leishmania amastigotes. Transmission electron microscopy revealed Leishmania amastigotes in the macrophage cytoplasm. All tissues with granulomas were positive for Leishmania spp, which was confirmed to be Leishmania infantum by conventional polymerase chain reaction (PCR), real-time PCR, and in situ hybridization. To our knowledge, this is the second case of canine visceral leishmaniasis in Korea.