Eribulin mesylate (eribulin) is a nontaxane microtubule inhibitor approved in Japan for treating soft tissue sarcoma irrespective of histological subtypes. Thus, our department routinely uses eribulin to treat any histological subtype of sarcoma for patients who have experienced disease progression during standard therapy. However, evidence on the efficacy of eribulin in treating sarcomas that are neither liposarcoma nor leiomyosarcoma is limited. Recently, we encountered a case of a heavily pretreated cardiac angiosarcoma that responded well to eribulin treatment. The patient was a 34-year-old Japanese woman with advanced angiosarcoma, who had been pretreated heavily using several lines of chemotherapy. Eribulin was administered as the eighth line of treatment and the dose was adjusted because of grade 4 neutropenia. After three cycles of treatment, contrast-enhanced computed tomography showed a partial tumor response, which was sustained for ~4 months. This case suggests that eribulin may be a potential therapeutic option for angiosarcoma. Further studies are needed to confirm the benefit of eribulin for patients with angiosarcoma and to establish predictive markers for eribulin sensitivity.