A 14 year old female spayed Beagle mix dog presented to her referring veterinarian (rDVM) for a 3-week history of inappetence, and hematuria without polyuria/polydypsia (Pu/PD), pollakiuria, or dysuria that had not responded to antibiotic therapy. Diagnostics performed by the rDVM included a complete blood count (CBC), serum chemistry, urinalysis, and ultrasound. The abnormalities noted were a mild increase in blood urea nitrogen (BUN) and alkaline phosphatase, and a mass-like lesion on the left kidney. A fine needle aspirate (FNA) and tru-cut biopsy were both non-diagnostic. The dog's owenrs were referred to the Cornell Univerity Hospital for Animals. At presentation to Cornell, the physical examination was mostly unremarkable except for a Grade IV/VI systolic murmur and perivulvar blood staining. Pre-operative diagnostics showed a mild regenerative anemia of 38%, mild azotemia, and a moderately sized mass in the cranial pole of the left kidney. The dogs was admitted to the hospital for supportive therapy and a nephrectomy. Surgery was completed without complication. Histopathologic evaluation of the left kidney was consistent with hemangiosarcoma. The dog recovered uneventfully from surgery and is doing well at home with no specific therapy.