Background: Recurrence is one the most important issue after thoracic surgery for pneumothorax, and the choice of additional chemical pleurodesis after surgery to eliminate recurrence remained unclear. Herein, we made prudent assessment of the safety and efficacy of chemical pleurodesis with picibanil (OK-432) for reduction of recurrence of pneumothorax. Methods: Between 1994 and 2014, 1,695 patients, who suffered from primary spontaneous pneumothorax (PSP), were treated by video-assisted thoracic surgery (VATS). After the operation, additional OK-432 was instilled into the pleural for chemical pleurodesis in 89 patients. The surgical outcome and demographic data of these patients were retrospectively reviewed. Results: The most frequent indications of surgical intervention were ipsilateral recurrence of pneumothorax (67.4%) and prolonged air-leakage (21.3%). There was no mortality and associated complication were as following, fever, intolerable pain, and post-operative effusion, wound poor healing. Median length of post-operative stay was three days. During routine post-operative follow-up, only two patients (2.2%) suffered from recurrence of pneumothorax and no additional surgical intervention was indicated. Conclusions: The long-term result of additional chemical pleurodesis, using OK-432 following VATS bullectomy is safe and effective with low recurrence rate (2.2%). Our experience suggested that OK-432 was a reliable sclerosing agent for chemical pleurodesis.