Desmoplastic small round cell tumor is an extremely rare and highly aggressive neoplasm. It usually arises as a single mass or multiple masses in the abdominal cavity, characterized by diffuse peritoneal implants, involvement of regional lymph nodes, and liver and lung metastases. However, bone marrow metastasis has rarely been reported in the literature. We present a case of clinically symptomatic bone marrow metastasis in a 25-year-old woman with a diagnosis of desmoplastic small round cell tumor originating from the pelvic cavity.