Mass examination of pulmonary function was carried out with 5, 345 children of elementary and middle schools in Gunma Prefecture, and from the results, prediction formula for the normal values of fast vital capacity (FVC) measured with the vitalor, peak flow rate (PFR) measured with Wright's peak flow meter were obtained. The prediction formula for FVC and PFR, as classified by sex, were obtained by two methods : Multiple regression equations between FVC and PFR on one hand and age and height on the other, and by regression equations between index for predicted vital capacity (FVC ml/height cm) and that for PFR (PFR 1/min./height cm) on one hand age on the other. The followings are the main findings : 1) Prediction formula for FVC for males, aged 7-12 years Y =22.83 × age+39.18 × height-3473.9 (multiple regression equation formula) Y = (3.930+ 1.117 × age) × height (index for pred. formula) for females, aged 7-14 years Y =170.80 × age+ 14.63 × height-1749.0 (MREF) Y = (1.582+ 1.248 × age) × height (IPFVC) (Y=estimated value of FVC, ml. Age is in years & height in cm) 2) Prediction formula for PFR for males, aged 7-12 years Y=8.2 × age+4.5 × height-411.7 (MREF) Y = (0.422+ 0.163 × age) × height (IPPFR) for females, aged 7-14 years Y =3.5 × age+5.6 × height-530.0..... (MREF) Y = (0.232+ 0.165 × age) × height (IPPFR) (Y =estimated value of PFR, 1/min.) 3) Comparison of the present results with the data for coastal inhabitants previously published by other institutions revealed that the former tended to be lower than the latter for younger group, aged 7-8 and 9 years. 4) The regression line obtained with the multiple regression equation was found better comf orming, than that of the formula for FVC index, to the scatter diagram between height and FVC for definite age range. As the consequence, the authers want to recommed the multiple regression equation for obtaining the predicition formula.