The effects of acute fluoride toxicity have been well documented in the literature. Drinking water is an important source of fluoride intake by humans, hence studies need to be carried out to determine the concentration of Fluoride in water. Therefore, this study tends to demonstrate the fluoride concentration in drinking water in thirty-one provinces of Iran during 2014. This cross-sectional study on drinking water was conducted in 2014. SPADNS method was determined for fluoride concentration examination according to instruction of Standard Methods. The minimum concentration of fluoride in provinces, such as Fars, Kermanshah, Kohgiluyeh and BoyerAhmad, Markazi, and Hormozgan, was observed to be 0.01 mg/L, while the maximum concentrations were observed to be 3.72 and 3.52 mg/L for Bushehr and Fars, respectively. The minimum and maximum average mean concentrations were 0.193 (SD = 0.11) and 0.889 (SD = 0.31) for Kermanshah and Bushehr, respectively. Due to the disadvantages of fluoride and because of the existence of different ecological conditions in Iran, there are different concentrations of water fluoride in the country. Therefore, proper policies should be made for water treatment plants based on the regional conditions in order to achieve a desirable fluoride concentration standard.