Objective: The purpose of this study was to investigate the fluoride concentration in drinking water in the Primorsko-goranska county (PGC) and to provide the guidelines for teeth fluoridation of respective area. Methods: Data on the fluoride concentration in drinking water in the PGC were examined by the Department of Environmental Health of the Teaching Institute of Public Health in Primorsko-goranska county. The fluoride concentration in the drinking water was measured by using ion chromatography technique. Public water supply in PGC is organized through 9 particular water supply systems. A high percentage of 96% of the population is connected to the public water supply, which is considerably higher than 74% representing the average estimation for the total country. Results: The average concentration of fluoride in the main water sources of the PGC was assessed for a 5-year period (2007-2011: Rijeka 0.010 mg F-/l, Opatija 0.020 mg F-/l, Crikvenica - Novi Vinodolski (CR-NV) 0.007 mg F-/l, Delnice 0.029 mg F-/l, Vrbovsko 0.038 mg F-/l, Čabar 0.031 mg F-/l, Krk 0.044 mg F-/l, Cres – Lošinj (CR-LO) 0.054 mg F-/l, Rab 0.090 mg F-/l. PGC public water supply systems do not include artificial fluoridation of the drinking water. Concentration of fluorides in the drinking water is considered low and ranges from the detected limit of <0.002 mg F-/l in Opatija to 0.220 mg F-/l in Rab, representing the overall average value of 0.034 mg F-/l. Conclusion: Considering the amount of fluorides in the drinking water, teeth fluoridation can be safely accomplished by individually adjusted doses of other fluoride agents.