PURPOSE: Even though emergent percutaneous pinning after closed reduction is the popularized treatment of the displaced type II and type III pediatric supracondylar fractures of the humerus, the timing of pinning still presents controversy. The purpose of this study is to suggest an appropriate surgical time without significant perioperative complications. MATERIALS AND METHODS: From April 1995 to January 2002, 179 consecutive patients who had undergone surgical treatment were selected. They were divided to 5 groups [A group: 8 hours or less following injury (24 cases), B group: from 9 to 16 hours (63 cases), C group: from17 hours to 24 hours (63 cases), D group: from 25 hours to 48 hours (18 cases), and E group: from 49 hours to 72 hours (11 cases)] and reviewed retrospectively to analyze perioperative complications and operation time. RESULTS: There was no significant difference between each group with respect to surgical wound infection, iatrogenic ulnar nerve injury, VIC, operation time and the necessity of reoperation (p>0.05). CONCLUSION: Within the parameters outlined in our study, we could not find the any meaningful correlation between surgical timing and occurrence of perioperative complications and also, we think that the timing of percutaneous pinning can be delayed to the time when a surgeon considers it appropriate.