Background : The purpose for this study is to develop a critical pathway of bullectomy for spontaneous pneumothorax patients. Methods : For this study a conceptual framework of critical pathway was developed through a review of the literature including five critical pathways which are currently being used in USA, and opinions of the critical pathway development team members at Y university hospital. In order to identify the service contents required by these patients and to draw up a preliminary critical pathway, 33 cases of medical records of patients who had received bullectomy for spontaneous pneumothorax between September, 2000 to August, 2001 at the Respiratory Center of Y university hospital in Seoul was analyzed. Results : In order to test the clinical validity of the preliminary critical pathway, it was applied to ten patients who had received bullectomy for spontaneous pneumothorax from October, 2001 to December, 2001. The average discharge day was 4.89th post operation day, six patients discharged on the fourth post operation day which was the expected day, one patients discharged one day earlier than the expected day, one patient discharged three days later than the expected day, and one patient discharged six days later than the expected day. There were variances between the critical pathway and the actual practice. The variances came from tests, medications, and treatments. One item that showed variance in clinical applications was complemented, and three items were decided not to be corrected for the final determination of the critical pathway. Conclusion : This critical pathway is applicable to the care of patients with bullectomy for spontaneous pneumothorax, but it needs more clinical applications to grasp varied variances.