Malignant melanoma is well known for its propensity to spread to unpredictable sites. F-18 FDG PET can highlight metastases at unusual sites that may be missed with conventional imaging modalities. In this study, we present the case of a 57-year-old male patient who was referred to our department for PET/CT imaging because of metabolic characterization of the lesion located in distal common biliary duct and biopsied as malignant melanoma. His PET/CT images revealed a hypermetabolic lesion at the mentioned site. Interestingly, his images also showed mild FDG accumulation on right frontoparietal skin, and the biopsy of this lesion was also reported as malignant melanoma.