ObjectivesThe postoperative recurrence rate after thoracoscopic bullectomy for primary spontaneous pneumothorax (PSP) is not satisfactory. This retrospective study was conducted to elucidate an effective technique for improving the postoperative recurrence rate.MethodsThe present study included 373 patients who underwent thoracoscopic bullectomy for PSP at three hospitals from January 2013 to May 2020. We compared the recurrence rate according to two methods that were used to cover the staple line after thoracoscopic bullectomy. Group A (146 patients) was treated with an absorbable polyglycolic acid (PGA) sheet plus fibrin glue and oxidised regenerated cellulose (ORC). Group B (227 patients) was treated with ORC alone.ResultsThere was no significant difference in preoperative characteristics of the patients. The postoperative recurrence rate of pneumothorax was 3.4% (5/146) in Group A and 17.2% (39/227) in Group B, respectively. Among 23 patients (Group A, n=3 and Group B, n=20) who received reoperation for recurrent pneumothorax, the site of recurrence was around the stapler line of the first operation in 1 of 5 (20%) patients in Group A and 28 of 39 (71.8%) patients in Group B. The 1-year recurrence-free rate was 97.4% (median follow-up period, 73 days (range, 2–3952 days)) in Group A and 80.9% (median follow-up period, 71 days (range 2–2648 days)) in Group B.ConclusionsCoverage with a PGA sheet may prevent the postoperative recurrence of PSP. A large-scale prospective randomised study should be conducted to clarify the most effective treatment for PSP.