Frontal saw-cuts of 60 human cranial fornices (age 1-21 years) served as the material for the investigation. By means of the microscope MBC-2 thickness of the bones was measured. The age changes of the bone thickness in the cranial fornix are approximated by the function of asymptotic growth TK' = 5.3-3.5 X 10(-0.14(X-1) (mm), where X = 1.2,..., 8 and logistic function TK' = 1/(1 + 10(11.4 - 0.74X) +4.93 (mm), where X = 8.9,..., 21 (years). Thus the bone thickness of the cranial fornix undergoes the pubertal spurt of growth, when the maximal rate in increasing thickness is noted between 15 and 16 years of age. This phenomenon should determine certain increase in dimentions of the skull during the pubertal period.