We examined the prevalence of dental caries at five nursery schools in Kyoto: A, K, N, KY and S. The number of children who entered each school under one year of age was 70, 71, 35, 5, and 0 percent respectively.<BR>The results obtained were as follows.<BR>1. The Prevalence of Dental Caries The ratio of children with carious teeth in nursery schools A, K and N was less than that in nursery schools KY, S, though the difference between the two groups decreased as the children grew older.<BR>2. Average Number of Def Teeth and Def Surfaces In nursery schools A, K and N, the average number of def teeth and def surfaces was less than that in KY and S.<BR>3. Dental Caries Attack Pattern In nursery schools A, K and N, there were more caries-free children and fewer numbers of children who revealed severe attack patterns of dental caries compared with those in KY and S.<BR>4. Comparison of the Prevalence of Dental Caries between Children who entered School N at less than One Year of Age and those who entered at more than One Year of Age The results sh o wed that children three, four and five years old who entered nursery school N when less than one year of age had fewer def teeth and def surfaces than those of the other groups.<BR>5. Results of The Questionnaire Children who en tered nursery school when less than one year of age had to give up the bottle or the mother's breast, had to stop drinking sweet drinks from a bottle and had to change their food from a liquid type to a solid typeat an early age. Their intake of sweets was regularized after entering nursery school. Their mothers had an opportunity to realize that dental decay is a preven table disease.<BR>Therefore, the earlier the regulation of nutritional intake, the smaller the possibility of the occurrence of dental caries.