The lung is a relatively rare site for mucosa-associated lymphoid tissue (MALT) lymphomas: we report the largest available single-center series of patients with this presentation. From August 1992 to October 2000, 12 patients with untreated primary low-grade MALT lymphoma of the lung were submitted either to chemotherapy alone (n = 8), surgery alone (n = 2) or surgery plus chemotherapy (n = 2). At diagnosis, 6 (50%) were asymptomatic and 6 (50%) had nonspecific pulmonary symptoms. The most common radiologic findings were a pulmonary infiltrate (7 cases) and a mass lesion (5 cases). Histological diagnosis was obtained with transbronchial lung biopsy/bronchoalveolar lavage (BAL) (6 cases), with transthoracic needle biopsy (1 case), or an open thoracotomy (5 cases). All patients had stage IE. All 12 (100%) achieved complete remission; 3 (25%) local recurrences were observed. The global 6-year survival rate was 100% with a relapse-free survival rate of 50%. In conclusion, these data underline the diagnostic utility of BAL and the therapeutic efficacy of a chemotherapeutic strategy based on regimens such as N-CVP in the context of localized MALT lymphoma of the lung.