Résumé : Apocrine skin carcinoma (ASC) is a rare aggressive cutaneous tumor. We describe a case of ASC occurring on a nevus sebaceus of Jadassohn (NSJ) in a 66‐year‐old man. Malignant degeneration of NSJ is a rare complication usually found in elderly patients. Most of these tumors are basal cell carcinomas or squamous cell carcinomas. Only five cases of ASC on NSJ have been previously reported. This report recalls the potential of NSJ for degeneration.