Background: Postural round back is a common entity with unknown etiology. Reports on the results of brace treatment are scarce. The purpose of this study was to determine the effect of bracing in different stages of treatment and also the amount of preservation of kyphosis after stopping the brace.Methods: from 1991 through 2005, 165 cases (39 male, 126 female) who had a diagnosis of idiopathic postural kyphosis were treated with a Milwaukee brace. The mean age at the initiation of treatment was 13.06 years (8-16 years), at the completion of treatment was 15.06 years (11-17 years) and at the final follow-up was 17.9 years (12-25 years). The mean initial kyphosis was 59.26° (51°-74°). The patients were evaluated after an average follow-up of 34 months (6-102 months).Results: The mean angle of kyphosis was 42° (28°-68°) at completion of treatment, and 47.9° (28°-75°) at the final follow-up. Angle of kyphosis was 50° or less in 85.9% at the end of treatment and in 74.7% of patients at final follow-up. 5.9 degrees of original correction was lost in final follow-up. Two cases underwent surgery. Brace was effective in correction of kyphosis (p < /em>=.001).Conclusion: Milwaukee brace is effective in treatment of postural kyphosis. Longer period of treatment, even after maturity, is needed in more stiff deformities.