In this report we describe what we consider to be the second case of seminal vescicle (SV) metastasis from an unknown primary melanoma. only presenting symptom was a palpable firm nodule of the right prostate base on digital rectal examination (DRE). The diagnosis, after prostatic transrectal ultrasound examination (TRUS), was performed by ultrasound guided biopsy. We underline that prostatic TRUS evaluation is mandatory in case of abnormal digital rectal examination. Seminal vesicle must be always evaluated.