The purpose of this study was to assess the prevalence of dental fluorosis and dental caries among 6-12 year old school children in Rewari district, Haryana, and to examine the relationship between the two. A total of 1195 children from six different areas with varying levels of naturally occurring fluoride in their drinking water were examined under natural daylight. Dental fluorosis and caries were recorded using the WHO index (1997) and Dean's Fluorosis index.The severity of dental fluorosis was found to increase with higher fluoride levels in drinking water, while dental caries decreased with an increase in fluoride concentration. Therefore, despite producing unacceptable and unaesthetic dental fluorosis, fluoride was shown to be an effective anti-cariogenic element. It can be concluded that government authorities should provide a central water supply to prevent the unwanted effects of fluorosis.