Extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) is usually indolent. Although it was reported recently that about 20-30% cases of MALT lymphoma presented with a disseminated disease at diagnosis, it was described as a disease localized at diagnosis and remaining stable for a prolonged period. However, only a few cases of MALT lymphoma involved the lung and gastrointestinal tract all at once. We report a case of a 73-year-old man with disseminated MALT lymphoma. He presented with non-productive cough, initial chest radiograph showed a nodule in the right lower lobe. The diagnosis of stage IV MALT lymphoma was made by CT scan, video-assisted thoracoscopic excisional biopy, gastrofiberscopic biopsy and bone marrow biopsy. The lymphoma involved the lung, stomach and bone marrow at the time of diagnosis. Because he refused chemotherapy, he discharged after Helicobacter pylori eradication without chemotherapy. Regular follow-up examination did not show any evidence of disease progression over 22 months.