Gaya district is located at 84.4-85.5_E longitude and 24.5-25.1_N latitude. In the south and east parts of this district, rocky terrain composed of foliated gneiss, a subdivision of the Archean system is found. Weathering and leaching of fluoride (F) bearing minerals lying in the joints, fractures and faults of these rocks under alkaline environment leads to the enrichment of F in the groundwater. Three hundred and thirty-three water samples were analysed from the hand pumps of 84 villages of the 24 blocks of Gaya district, Bihar. F level was measured by using Fluoride Ion selective electrode Orion 9690 BNWP with PCD 650 cyber scan portable meter. Commercially available Ion strength adjusting buffer i.e. ISA I was added to the samples before the estimation of fluoride. Bodh Gaya block with F level less than 1 mg/L (Mean = 0.59 ± 0.03 N = 11) was considered as control area, while Amas and Bankebazaar blocks were F endemic areas, with mean F level 2.36 ± 0.23 (N = 27). The residents of F endemic area were found to suffer with dental, skeletal, and non-skeletal fluorosis.