Synovial sarcoma is a mesenchymal spindle cell tumor. Primary pancreatic sarcomas are extremely rare. The present study describes a rare case of synovial sarcoma in the head of the pancreas. A 35-year-old male presented with left upper quadrant abdominal pain. An endoscopic ultrasound examination revealed a complex solid-cystic lesion in the pancreatic head. He had undergone pancreaticoduodenectomy (Whipple procedure). A histological examination yielded negative results for AE1/AE3, CD10, S100, CD34, desmin, smooth muscle actin, β-catenin, CD117, HMB45, chromogranin and synaptophysin. However, the results were positive for TLEI and vimentin, which is consistent with synovial sarcoma. Synovial sarcoma is a soft tissue malignant tumor. Primary pancreatic sarcomas frequently present as large, high-grade tumors in the pancreatic head. Histologically, there are several types of synovial sarcoma, such as monophasic, biphasic and poorly differentiated. A histological examination is necessary for the diagnosis as the imaging findings are not specifically suggestive of synovial sarcoma. The preferred course of treatment is complete resection with wide margins, followed by adjuvant chemotherapy and/or radiotherapy. Primary mesenchymal tumors of the pancreas are extremely uncommon. As a result, a diagnosis requires careful evaluation. Surgical resection is the main modality of treatment.