Water-rock interaction is one of the prime factors affecting the fluoride contents of surface and groundwater. If fluoride concentration of drinking water has been neglected, excess fluoride can cause serious dental and medical problems on human health, which is well known at Golcuk-Isparta region. In the research area, Egirdir lake, Golcuk lake and surrounding springs have been utilized as drinking water sources. Golcuk lake water and surrounding groundwaters have high fluoride content (1.4-4.6 mg/l), which is above the WHO standards. Fluoride is predominantly supplied by dissolution of fluoride within the fluormicas of volcanics during the circulation of water. Fluoride concentrations of waters have shown variations for dry and rainy seasons depending on the degree of interaction between groundwater and volcanic rocks. It tends to decrease in rainy seasons and increase in dry seasons for all years. In this study, temporal variations and spatial distribution of fluoride concentration in public water system of Isparta were investigated to get benefit using GIS techniques from1990 to 2003 years. Extremely fluoride concentrations were measured in the public water system in 1990 at almost every district of the city. In 2003, fluoride content of the public water system decreased in some district of city due to drinking water has started obtaining from Egirdir lake in 1995. The fluoride contents of Isparta drinking water ought to be modified with suitable mixture of lake waters and groundwater point of view to health impact.