Introduction: Oral health is a crucial component of general health, with dental caries affecting a person's ability to eat, speak or socialize. There is a high prevalence of dental caries worldwide involving the people of all region and society. Schools provide a platform for the promotion of health and oral health not only for the students, but also for the staff, families, and members of the community as a whole. Aim: To determine the prevalence of dental caries in the primary and permanent teeth, and evaluate the brushing habits of school children. Material and Methods: This is cross-sectional short study was carried out in Nangal Raya Village , New Delhi district to assess the prevalence of dental caries among Government and public school children in the age group of 6–12 years. We covered 11, Government and public schools and examined and selected 2350 children with random sampling. The examination of dental caries was assessed using DMFT index (Klein, Palmer, Knutson 1938). Results: The caries prevalence and mean dmf scores in children who brush once daily 66.2% (Mean dmf 2.5) was higher than in those children who brush twice a day 50.6% (Mean dmf 2.1). These results were very highly significant The caries prevalence and mean DMF scores in children who brush once, twice and after every meal were 15.3% (Mean DMF 0.20), 23.8% (Mean DMF 0.31) and 14.7% (Mean DMF 0) respectively. This showed that caries prevalence was maximum in the children who brush once daily compared to other frequencies of brushing. These results were highly significant.