We report a 70-year-old man with asymptomatic reddish papules on the glans penis that histologically showed metastases of prostate adenocarcinoma. He had a medical history of a stage IV undifferentiated prostate adenocarcinoma that was currently being treated with chemotherapy. The medical history of advanced stage prostate adenocarcinoma associated with the clinical and pathological findings confirmed the diagnosis of penile metastatic prostate adenocarcinoma. This is an example of the relevance of a thorough history combined with histopathological and immunohistochemical correlation which allowed the diagnosis of a penile lesion that may be the first manifestation of prostate metastatic progression and should therefore be included among the differential diagnoses of penile tumors.