A 61-year-old man was admitted to our hospital with extreme weight loss. Abdominal ultrasonography revealed an 8-cm tumor of the pancreatic head. Further investigation revealed orbital, pulmonary, pancreatic, colonic, and bone marrow lesions. A histopathological examination of the pancreatic tumor specimen obtained using endoscopic ultrasound-guided fine-needle aspiration revealed mucosa-associated lymphoid tissue (MALT) lymphoma. Monoclonal rearrangement of immunoglobulin heavy chain was found in the pulmonary, pancreatic, colonic, and bone marrow lesions. We diagnosed multi-organ disseminated MALT lymphoma, with the largest lesion located in the pancreatic head. Chemo-radiation therapy resulted in complete remission.