A 13-yr-old intact male cheetah (Acinonyx jubatus) presented for evaluation after a 4-mo history of intermittent lethargy and increased expiratory effort. The clinical signs were initially noted after the diagnosis and death of its 13-yr-old male sibling with solitary hepatic T-cell lymphoma. Physical examination findings included thin body condition, harsh lung sounds, peripheral lymphadenopathy, and a cutaneous mass on the right medial tarsus and scrotum. Excisional biopsies diagnosed well-differentiated cutaneous hemangiosarcomas. Thoracic radiographs revealed a cranial mediastinal mass. Complete blood count and serum biochemical analyses showed a leukocytosis with persistent lymphocytosis, progressive azotemia, and markedly elevated alkaline phosphatase. Because of the cheetah's declining quality of life, euthanasia was elected. Postmortem examination, histopathology, and immunohistochemical staining revealed multicentric T-cell lymphoma. Feline leukemia virus (FeLV) enzyme-linked immunosorbent assay, FeLV polymerase chain reaction (whole blood), and viral metagenomic analysis were negative. This is the first case of cutaneous hemangiosarcoma and multicentric T-cell lymphoma reported in a FeLV-negative cheetah.