Alveolar soft-part sarcoma usually arises from the soft tissue of the lo0wer extremity, but may arise from the orbit, retroperitoneum and else where, in both children and adult. The tumor grows slowly, may invade the underlying bone, eventually may metastasis widely through the blood stream, Recently, we experienced 5 cases of alveolar soft-part sarcoma originated from thight, lower leg, inguinal region, retroperitoneum and orbit. the radioloigic findings are soft tissue mass(2 cases) with underlying bony destruction (3 cases), lung metastasis(2 cases). Although rare, alveolar soft-part sarcoma should be included in the differential diagnosis of soft tissue tumor arising from the lower extremity.