Coal mining will lead to acidification or salinization of groundwater, affecting the safety of coal mine production. In order to explore the chemical evolution of groundwater under the influence of exploitation, taking Qinglong Coal Mine in Guizhou Province as an example, combined with hydrochemical analysis and numerical simulation technology, a numerical model of groundwater was established to explore the evolution law of regional groundwater dynamic field and hydrochemical field under mining conditions. The results show that under the influence of water pumping during the mining process, the groundwater flow field changes, forming a falling funnel and forming a new watershed in the southwest. The main anions and anions were concentrated at the pumping well, and the concentration change in the first 5 years was more obvious than that in the last 5 years, and the hydrochemical type of Changxing Formation changed from HCO3-Ca type to HCO3-Na、Ca type due to the influence of leaching and cation adsorption, and the concentration of HCO3- increased, which may have a corrosive effect on underground equipment