PURPOSE: To evalute the anatomical and functional outcome after treatment for proximal humerus fracture according to surgical and conservative treatment and assess the final results according to treatment methods. MATERIALS AND METHODS: Forty-two cases with follow-up over 12 months were divided into three groups: conservative treatment (Group 1, 20 cases), closed reduction with Rush or percutaneous pin fixation (Group 2, 11 cases), proximal intramedullary interlocking nailing(Group 3, 11 cases). The functional outcome was obtained by modified neer method using self-assessed score paper and the anatomical outcome was obtained by paavolainen method using radiologic film score. Statistics in comparing with the result of each group was analized by variance analysis using Generalized Liner Model and Fisher?s exact test. RESULT: Anatomical reduction was best obtained in group 3 (p< 0.05) and mean duration of bone union was 10.33 weeks. Functional score was also best obtained in group 3 (p<0.05). Complication was noted in 9 cases. There was only 1 case in group 3. In studing of overall outcome, the group 3 has good result than other groups. CONCLUSION: Proximal intramedullary interlocking nailing in displaced proximal humerus fracture can be demonstrated as better method for anatomical reduction(p<0.05) than other methods because it can make insertion of locking screw ease with multiple direction for anatomical reduction and can provides a sufficient fixation for early rehabilitation and union , while minimizing complication.