Caries remains an important dental problem in childhood. The resistance of teeth to caries is due to the resistance of the enamel, the formation of which depends on a signifi cant number of general and local factors.The aim of the research. Study of acid resistance of enamel in children of diff erent ages and with diff erent dental status.Material and methods. We surveyed 134 children aged 7-9 years and 89 children aged 10-12 years who study in schools in Poltava. Dental examination was performed according to the generally accepted method. In all children, the intensity of caries. To determine the resistance of tooth enamel to caries used the test of enamel resistance according to Okushko VR, Kosareva LI.Results. The average enamel resistance test in children 7-9 years is 4.07±0.11 points. During the division of children into groups with and without caries, signifi cant diff erences were found (4.67±0.10 points and 2.59±0.09 points, respectively).In children aged 10-12 years, the average enamel resistance test is 4.29 ± 0.12 points, which corresponds to moderate enamel resistance. In children with caries of temporary and permanent teeth, it is also moderate (4.67±0.09 points), but the numerical values are slightly worse than average. In children 10-11 years with caries of temporary teeth, the enamel resistance test index is almost no diff erent from that of children with intact temporary teeth. We found that the rate of caries of temporary and permanent teeth has a direct correlation with the test of enamel resistance (R=0.76; p<0.001).Conclusions. The course of caries in children 7-12 years is due to reduced resistance of teeth to caries, as evidenced by the results of the study of acid resistance of enamel on the test of enamel resistance.