The biting force value of normal teeth of 770 human subjects were measured by electric resistance strain gnathodynamometer. 365 were males, and 405 females. Their ages ranged from 13 to 49. The results showed that the biting force value of males is larger than that of the females (P < 0.01). In the males, the biting force value of those aged 13-16 gradually increased with age, and the maximal biting force values of incisor, bicuspid, and first molar of all the males were 43.3kg, 99.11kg, and 120.66kg respectively.