Objective To explore the differences of bone age of radius,ulna,metacarpophalangeal and carpal bones in children with different physiques.Methods Radiographs of children's wrists aged between 4 and 12 years were collected.The bone age of radius,ulna,metacarpophalangeal,and carpal bones were assessed using the Chinese Children's Bone Age Score,and the difference between the two bone ages(the former minus the latter)was recorded.According to gender,age,and physical grouping,the physical group was divided into normal and abnormal groups.The abnormal group was further divided into thin,overweight,and obese groups.A comparative analysis was conducted to determine the differences in bone age between normal and abnormal groups for both males and females at all ages.Results A total of 3 028 children were included,and the differences between the two bone age results for normal boys aged 7-12 years and normal girls aged 5-12 years were not statistically significant(P＞0.05).In boys,there was no significant difference in bone age between the normal group and the thin group(P＞0.05),the difference in bone age between the normal and thin groups at the age of 5-6 years was greater than that between the overweight and obese groups,and the difference was statistically significant(P＜0.05),the difference in bone age between the normal group at 11-12 years and the thin group at 11 years was smaller than that between the overweight and obese groups(P＜0.05).The difference in bone age was smaller in the normal group than in the thin group at 6 years of age for girls(P＜0.05),and larger in the thin group than in the overweight and obese groups at 5 to 6 years old(P＜0.05).Conclusion The difference in bone age between the TW-C RUS series and TW-C C series bone age values is influenced by the child's gender,physique,and age.The difference in bone age between the majority of normal children and the thin group is not statistically significant,but differed from the overweight and obese groups at some ages,most are the overweight and obese boys.