Pancreatic tumors are primary in most of the cases. Pancreatic metastases associated with other primary malignancies, especially pancreatic metastasis of leiomyosarcoma, are uncommon. A 66-year-old woman underwent surgical resection of malignant mesenchymoma (70% osteosarcoma and 30% leiomyosarcoma) in the right thigh. In the postoperative period, a pancreatic mass was identified radiologically by abdominal computed tomography. Pylorus-preserving pancreaticoduodenectomy was performed. The surgical specimen revealed leiomyosarcoma metastasized to the pancreas. A metastatic nodule on the remnant pancreatic tail was discovered 9 mo after the first pancreatic resection, and distal pancreatectomy was performed. Cases of pancreatic metastasis from leiomyosarcoma are extremely rare, especially when the tumor was resectable. We report here a unique case of pancreatic metastasis from a leiomyosarcoma in the right thigh that had been treated surgically.