Canine Transmissible Venereal Tumor (CTVT) also known as venereal sarcoma is an inflammation mediated by reticuloendothelial tumors and infects the canine genitalia. This study aimed to diagnose CTVT cases in domestic dogs by looking at clinical symptoms, macroscopic, hematologic, blood chemistry and cytology, a n d a l s o by histopathological features. Based on clinical symptoms or anatomical pathology (macroscopic) on CTVT was appears in the form of lumps and blood mucus on the vestibule. On the vulva were visible hemorrhagic fluid secretions. The nodules that form on the genital organs resemble cauliflower and they were fragile, hyperemic, hemorrhagic and multilobular masses. Hematological and cytological examinations showed a decrease in the value of red blood cells, hemoglobin, and hematocrit which as a sign of anemia and showed increase in aspartate transaminase (AST), alanine transaminase (ALT), glucose, and ureum values. Meanwhile, the decrease occurred in total protein, albumin, globulin, and A/ G ratio. The results of the CTVT histopathology examination by biopsy of vulva vagina indicate perivascular inflammatory cell infiltration, neovascularization, and proliferation of fibroblast cells accompanied by necrosis and the formation of cytoplasmic vacuole. This paper is expected to increase knowledge and information about confirmation of case diagnosis canine transmissible venereal tumor on domestic dog.