A case of extrastkeletal Ewing's sarcoma on lower extremity in a 60-year-old male is reported. Extraskeletal Ewing's sarcoma is a rare malignant neoplasm that shows similar histologic and ultrastructural features to Ewing's sarcoma of bone. Histologically, the neoplasm was composed of small, round to oval cells with scant cytoplasm that were arranged in sheets with large area of necrosis. Electron microscopy of the neoplastic cells revaled scant cytopasm containing glycogen rosettes and a paucity of organelles. There is no ultrastructural evidence to indicate the origin of the cells.