Objective: This study aims to measure the concentration of fluoride in groundwater consumed by Laos students and provide basis data for conducting a future fluoride supplementation project. Methods: The groundwater consumed by students was collected from urban and rural elementary and high schools in five regions of Luang Namtha, Luang Prabang, Vientiane, Savannakhet, and Pakse in Laos, and the fluoride concentration of the groundwater was measured. Results: The highest fluoride concentration was 0.410 ppm in rural elementary schools in Pakse Province, and 0.000 ppm in most of Vientiane Province. The average fluoride concentration, including the 0 value, was 0.075 ppm, and the average fluoride concentration excluding the 0 value was 0.089 ppm. Conclusion: The groundwater fluoride concentration in all five regions of Laos was found to be below the appropriate drinking water fluoride concentration of 0.700 ppm.