Abstract: [Objective] To explore the feasibility and accuracy of Three-dimensional Printing(3DP) combined navigation template assisted by computer-aided Design (CAD) and 3DP in children with temporary epiphysiodesis of lower extremity deformity.[Methods] From January 2016 to December 2018, a total of 37 children with knee deformity (10 cases of genu varus and 27 cases of genu valgus) requiring temporary epiphysiodesis with 8-plate were included in the study. They were randomly divided into traditional surgery group(17 children) and navigation template group(20 children). The general data, clinical results and imaging evaluation results were compared.in both group.[Results] All the 37 patients had operation performed successfully without serious complication. Compared with the traditional surgery group, the mean operative time of each 8-plate and the average number of X-ray exposures were significantly reduced (P<0.05). In term of radiographic evaluation, The deformities of lower extremities in both groups were corrected, and there were significant differences in FTA, mMPTA and mLDFA at the latest follow-up compared with those before operation(P<0.05).[Conclusion] The individualized 3DP navigation template designed in this study reduces the operative time and the number of intra-operative X-ray exposure times for epiphysiodesis with 8-plate for children with lower extremity deformity, and can assist the precise placement of 8-plate.