This article investigates the distribution of the essential elemental fluorine in groundwater from the entire area of Shandong Province, which has endemic fluorine disease. Based on 4321 groundwater inorganic analysis data collected between 2006 to 2016, the distribution characteristics and driving mechanisms of fluorine enrichment in groundwater in Shandong Province were studied in detail using mathematical statistical analysis, ion ratio analysis, and water chemical equilibrium system analysis methods. The results show that the shallow high fluoride groundwater was contiguously distributed in the low- lying areas of the Jiaolai basin and the Southwestern Plain of Shandong. The area where shallow groundwater fluorine concentration exceeds 1 mg/L is 13227 km2, with a fluorine concentration maximum of 22 mg/L. The deep pore confined groundwater with high fluoride is concentrated in the deep groundwater depression funnel areas of Dezhou, Binzhou and Heze. The area where deep pore confined groundwater fluorine concentration exceeds 2 mg/L is 15086 km2, with a fluorine concentration maximum of 7. 5 mg/L. Groundwater extraction is the main factor driving fluorine enrichment in deep pore water. The average concentration of fluorine in different types of groundwater in decreasing order is deep pore confined groundwater, shallow pore groundwater, bedrock fissure water, fissured karst water, and pore fissure water. The fluoride concentration of deep pore confined groundwater has a significant negative correlation with Ca 2+ concentration that is not obvious in other types of groundwater. It is concluded that the formation of high fluoride groundwater in the Shandong Province is driven by three factors i.e. geomorphology and geological structure, geochemical characteristics of the aquifer medium, and human groundwater extraction. Leaching, evaporation and water- rock interactions further increase the groundwater fluorine content, and the fluorine- calcium incompatibility ultimately determines the fluorine content in groundwater. This study revealed the key factors controlling the fluorine enrichment of different types of groundwater and deepened the understanding of the chemical behavior of fluorine in groundwater.