A case of soft-tissue fibrosarcoma with pulmonary metastases in a dog is reported. Although three attempts of fine-needle aspiration (FNA) biopsy failed to provide definitive tumor diagnosis, results of angiography strongly indicated a soft-tissue sarcoma. Transcatheter arterial embolization (TAE) using particles of gelatin sponge was performed following selective angiography. The mass was decreased in size on reevaluation 2 weeks after embolization. The dog was euthanized on the request of the owners due to overall failing health. Necropsy and pathological study confirmed the diagnosis of soft-tissue fibrosarcoma with pulmonary metastases. In a review of the literature, angiographic findings of soft-tissue sarcoma in the dog of this report were similar to those in human beings, suggesting a potential role for angiography in the differential diagnosis of suspect soft-tissue fibrosarcomas and for guiding FNA or surgical biopsy. Previous reports have also shown therapeutic embolization to be an effective treatment both in experimental animal study and in clinical practice in the human; therefore, TAE could be an effective adjunctive treatment of soft-tissue fibrosarcoma in the dog.