Abstract: The Qingduo karst groundwater wellfield is a large-scale water-supply source in the city of Jiyuan in Henan Province. In recent years, trace amounts of heavy metals have been detected in groundwater around the wellfield to which high attention has been pain by the relevant departments and hydrogeologists. Identifying the recharge source and flow path to the karst groundwater, and the relationship between the karst groundwater and the overlying Quaternary aquifer, and recognizing the risk of heavy metal pollution are important in the protection of the water source. Based on the results of chemical and isotopes analyses of groundwater in the wellfield area in 2016, we examined the hydrogeochemical processes and the recharge sources of the groundwater. The results show that the major cation components in the karst groundwater mainly come from the incongruent dissolution of aragonite, calcite and dolomite in carbonate rocks and the main recharge resource of the karst groundwater is the precipitation in the northern mountainous areas. The significant differences in hydrochemistry and stable isotopes among different wells come from different pumping depths and recharge processes. High concentrations of Cl^- and in some of the karst groundwater indicate that they may be affected by the upper Quaternary aquifers or human activities, which should be paid more attention by relevant departments.