Skeletal muscle is one of the most unusual metastatic sites for any malignancy. Duodenal cancer is extremely rare, and no cases of skeletal muscle metastasis from duodenal cancer have been reported. We report here in a case of metastasis to the skeletal muscle of the left thigh from duodenal cancer. Our patient was a 47-year-old man, exhibiting a painful mass in the posterior aspect of his left thigh over a 4 month period. An imaging study, and a biopsy, revealed a duodenal adenocarcinoma metastasize to the skeletal muscle. The patient refused chemotherapy and has followed up for 4 months.