A 42-year-old male...showed a high-grade myxofibrosarcoma...About 40% to 50% of tumor cells in his pulmonary tissues were showed positive PD-L1 expression and his tumor mutational burden was 215Muts....initiating immunotherapy of Camrelizumab, the size of lesion 1 (12.4 mm × 9.0 mm) and lesion 2 (16.5 mm × 13.2 mm) were stable...patient was observed in good condition, exhibiting a sustained durable response...myxofibrosarcoma with no response to conventional therapeutic options, immunotherapy is a promising selection.