Malignant eccrine acrospiromas are rare. Clinically, they resemble other cutaneous lesions. A high index of suspicion must be maintained in cases of histologically benign eccrine acrospiromas for three reasons: (1) malignant transformation can occur, (2) the presence of both benign and malignant tissue can lead to a false-negative diagnosis if only the benign component is obtained in the biopsy specimen, and (3) benign-appearing tumors can recur locally or metastasize. The primary treatment is wide local excision with or without lymph node dissection. The efficacy of adjuvant chemotherapy and radiation therapy requires further investigation. We describe a case of malignant eccrine acrospiroma in an 80-year-old man, and we review the literature on this tumor, with emphasis on the differential diagnosis.