Abstract: Congenital dislocation of the hip （CDH) is a disease affecting the geometry of paedomorphic hips.In this paper,a software environment for measuring in surgical planning of pediatric hip orthopedics is developed to allow the surgical operation more feasible.An application of three-dimensional mirror transformation to virtual boned surgery is presented in the paper.By means of three-dimensional measurement,surgeons could be in a well condition to make virtual surgical plans and evaluate the results of surgical operations of congenital dislocation of the hip joints in the virtual environment.