This study was conducted to investigate dental caries according to obesity in order to provide basic data for efficient dental health program for elementary school students. Data were obtained from a health record book of 668 elementary school students in Chun Cheon city in 1998. Obesity was categorized into overweight. normal and under weight groups by Rohrer index. Dental caries was classified into decayed. filled and missed teeth. The result were as follow: 1. Prevalence rate of dental caries(dft) was $78.7\%$ and mean dft was 2.96; decayed and filled teeth was 1.01 and 1.95. respectively. As for mean dft. a siginificant difference were shown according to obesity and age. while no siginificant difference was shown between boys and girls. 2. Prevalence rate of dental caries including missed teeth (dmft) rate was $83.9\%$ and mean dmft was 3.64. As for mean dmft. a siginificant difference were shown according to obesity and age. while no siginificant difference was shown between boys and girls.