PURPOSE : to appreciate the effectiveness of th closed reduction and percutaneous pinning(CRPP) in reducible but unstable displaced surgical neck fracture of the humerus. MATERIALS AND METHODS : reviewed 30 patients(19 cases in CRPP and 11 cases in ORIF) with at least 1 year follow-up, comparing clinical union time, elapse time for surgery and clinical results using UCLA end-result scoring system in two froups and determining prognostic factors in CRPP. RESULTS : Clinical union was seen 8.4 weeks in CRPP and 11.2 weeks in ORIF. The difference between two groups in the clinical results was not significant. Lower UCLA score in CRPP correlated with the increment in age(p<0.05), but not with sex and metaphyseal comminution. Elapse time for surgery was taken average 38minutes in CRPP and average 95 minutes in ORIF. The postoperative complications in CRPP were 1 in nonunion, 4 in stiffness and 4 in pin loosening, most of them were occurred in female over sixty. SUMMARY : CRPP is a useful alternative and may be primarily applicable method in respect of comparable results to ORIF, minimal soft tissue damage and shorter surgical time. However, in cases of female with sixty or more, ORIF would be preferred because of poor bone quality, less compliant, and frequent joint stiffness.