The bone mineral density(BMD) of the lumbar spine (L2L4) was measured by using dual energy x-ray absorptiometry(Norland M6 DEXA) in 80 children aged between 2months and 15years (group I:2monthlyears, group 2: 1year5years, group3:6years10years, group4*: 11years15years). The correlation coefficient of BMD with age, body weight, height and Tanner stage were 0.696, 0.693, 0.717 and 0.636 respectively. There were sigificant difference. in BMD(g/cm2) between-group 1(BMD : 0.335 0.175) and group 2(BMD : 0.627 0.200), and group 3(BMD : 0.714 0.189) and group.4(BMD : 0. 8730.163) (P<0.05). There was no significant difference of BMD between boys and girls(P<0.05). BMD also increased significantly with development of Tanner stages(Tanner stage 1 : 0.547 0.234, Tanner stage 2 : 0.783 0.136, Tanner stage 3 : 0.998 0.080) (P<0.05). These data indicate that the BMD was correlated with age, body weight, height and Tanner stage significantly and BMD increased significantly during growth spurt occured in 1 to 4years of age and puberty.