Primary cutaneous leiomyosarcoma is a rare neoplasm. The tumor presents as a nondescript subcutaneous mass, and may be painful or tender. The diagnosis depends on the histopathologic findings. We report a case of primary cutaneous leiomyosarcoma developed in a 57-year-old male. Five and half years ago, the patient noticed a rice grain sized nodule on the right deltoid area. Five years ago, the lesion was excised at a local medical office. From 2 years ago, the tumor recurred on the excision site as a well defined painful erythematous hard tumor, measuring 3.5*3cm. Biopsy specimen showed densely packed, interlacing bundles of smooth muscle cells which have numerous anaplastic nuclei, atypical giant cells with bizarre nuclei and 10 mitotic figures per 10 high power fields.