Clear cell sarcoma is a rare malignant soft tissue neoplasm that usually arises adjacent to tendons or aponeuroses. The clinical course is rather slow, with repeated local recurrences followed by late metastases and eventual death. The principal sites of this neoplasm are the extremities, but tumors do occur in the trunk on rare occasions. We report a case of clear cell sarcoma arising from the chest wall. The patient, a 20-year-old woman, had noticed a chest wall mass and pain for 2 years. Biopsy of the mass showed abundant nests of round cells with clear cytoplasm. On immunohistochemical examination, tumor cells were strongly immunoreactive for S-100 and HMB-45. A diagnosis of clear cell sarcoma was confirmed. There was no other lesion found in the patient through routine imaging studies. She was treated with two courses of chemotherapy using ifosfamide, carboplatin, and etoposide. Subsequently, the tumor, including adjacent tissue, the chest wall, and sternum, was resected with a wide margin; and the defect of the chest wall was covered with Marlex mesh fabric, regin, and a musculocutaneous flap. She has shown no symptoms or signs of recurrence during 2 years of follow-up.