Objective To define the value of the center-edge angle (CEA) of normal hips in a healthy Chinese population. Methods The classical center-edge angle (CCEA) and modified center-edge angle (MCEA) were measured on the anterior-posterior pelvic radiographs of 1494 healthy Chi-nese older than 4 years. According to their ages,the enrolled individuals were divided into different groups: in the individuals aged 4 to 18 years old,they were grouped by year; in the individuals over 18,they were grouped by 10 years. The reference range of each group and the CEA corresponding to age were analyzed statistically. Results The mean CEA of 4-year-old group was 21.62°,which in-creased to 25.07° in 9-year-old group and to 32.14° in 18-year-old group. In healthy individuals over 18 years old,it fluctuates between 30° and 34°. Type Ⅲ acetabular rooves according to Ogata classifi-cation mainly appears in 4-9 years old groups,in which the difference between CCEA and MCEA is 10-12°. Conclusions CEA increases fast from 10 to 14 years old. Type Ⅲ acetabular rooves mainly ap-pears in 4-9 years old groups,when it is normal if CCEA is above 25°and MCEA is above 15°.