Abstract [Objective]: To investigate the clinical efficacy and safety of closed reduction short leg cast fixation of developmental dysplasia of the hip (DDH) in infants. [Methods]: We retrospectively reviewed a total of 121 DDH children with age from 6 month to 18 months. The patients were divided into group A (closed reduction short leg cast fixation) and Group B (closed reduction standard human position cast). 58 patients with 76 hips in group A, 63 patients with 80 hips in group B. The clinical efficacy was analyzed by comparing the frequency of fluoroscopy, the duration time of casting, the cast pressure ulcer happening, the time of start standing and start walking after removing the cast, Severin radiological assessment, the rate of redislocation, the incidence of femoral head avascular necrosis, and the evolution of the acetabular index.[Results] Excluding T?nnis typeⅡ hips, 9 hips were dislocated in group A, the redislocation rate was 18.4%. In group B, 2 hips were dislocated, the rate of redislocation was 3.9%. The redislocation rate of group A was higher than group B, the difference was statistically significant. Comparing the frequency of fluoroscopy, the duration time of casting, the cast pressure ulcer happening, the time of start standing and start walking after removing the cast was not statistically significant . At the last follow-up, the acetabular index of the two groups was significantly improved compared with before treatment. There were no significant differences in acetabular index, CE Angle and Severin grade between the two groups. Femoral head necrosis occurred in 10 hips in group A and 13 hips in group B, There was no significant difference in the incidence of femoral head necrosis between the two groups; [Conclusion]: Close reduction short leg cast fixation is one of the effective treatment choice for developmental dysplasia(dislocation) of the hip with age from 6 month to 18 months. The incidence of redislocation rate higher than standard human position cast in T?nnis Ⅲ、Ⅳ type DDH.