Abstract: Tanner--Whitehouse( TW2 )method, the Atlas method and Scorring system ( Li Guozhen ) skeletal age assessments were made in the school children sample of 275 males and 278 females aged 7--12 years in the Northern Chinese city of Harbin. The accuracy of skeletal age assessed respectively by three kinds of methods was compared each other. Wefound that Tanner-White house method was not fit for assessment of skeletal maturity onthe Northern Chinese school children of Han nationality. The Tanner- -White house skeletal ages were markedly greater than the corresponding chronological ages. The scorring systen( Li Guozhen ) skeletal ages were similar to the chronological ages as were Harbin Atlas skeletal ages.

Key words: School children; Skeletal maturity; TW2 method