Objective To evaluate the incidence and characteristics of spontaneous pneumothorax in patients with Marfan syndrome (MFS), and to analyze its related factors. Methods The medical record of patients with MFS who were hospitalized in the First Affiliated Hospital of University of Science and Technology of China from March 1, 2017 to December 31, 2022 were retrospectively collected, to analyze the incidence of pneumothorax and related risk factors. Results A total of 53 patients (including 29 males, 55%) were included, with a median age of 32 years (ranging from 13 to 65 years). All patients denied family history of pneumothorax. Four cases (8%) had one episode of spontaneous pneumothorax, with pulmonary bullae involved the ipsilateral apex. Among them, 3 cases (75%) had single pulmonary bulla and thoracic deformity. Of the 49 patients without previous pneumothorax history, 9 (18%) had pulmonary bullae, of which 6 (67%) were located at the apex of the lung, and the remaining 3 (33%) were in the middle and lower lobes of the lung; In addition, 6 cases (12%) were coexisted with thoracic deformity. The incidence of pneumothorax in patients with pulmonary bullae in MFS was significantly higher than those without pulmonary bullae (31% vs. 0%, P=0.002), and the incidence of pneumothorax in patients with thoracic deformities was significantly higher than those with normal thorax (33% vs. 2%, P=0.013). Of the 4 patients with pneumothorax, 2 underwent bullectomy, 1 underwent thoracic drainage, and the other underwent thoracic puncture and aspiration procedures, respectively. No recurrence of pneumothorax was observed during the follow-up period. Sixteen cases of MFS with spontaneous pneumothorax (11 males, 69%) were reported in Chinese literature, with a median age of 17 years (ranging from 13 to 28 years). Among them, 3 cases (19%) had a family history of pneumothorax, and 14 cases (88%) had thoracic deformities. Bullae was found in all 5 patients with pneumothorax, 4 of them with chest CT images involved the ipsilateral upper lobe. Forty-four percents of 16 patients had pneumothorax recurrence. Conclusions The incidence of MFS complicated with spontaneous pneumothorax is significantly higher. However, most of them have no family history of pneumothorax. The incidence of pneumothorax with MFS is associated with pulmonary bullae (especially the apex of lung) and thoracic deformity. Timely surgical intervention should be carried out when pneumothorax happened.