Abstract: In view of the increasingly stringent discharge requirements of coal mine water, this paper systematically evaluates the removal effect of traditional mine water purification technology on dissolved pollutants by using the existing purification process of a coal mine in southwest Shanxi. The results show that the mine water can not only effectively remove high-concentration particulate matter, but also remove dissolved pollution components such as organic matter, total phosphorus, fluoride, sulfide and total mercury to varying degrees. The enhanced purification measures of activated carbon adsorption and microfiltration can ensure that all dissolved pollutants except total nitrogen and fluoride can stably meet the Class III standard of surface water in the environment of large fluctuations in the concentration of pollutants in the raw water of the mine. Further studies found that the adsorption of particulate matter and activated carbon in mine water and the mechanical retention of microfiltration membranes were the mechanisms for the purification and removal of dissolved pollutants. In order to improve the purification effect of total nitrogen and fluoride, it is suggested to add denitrification denitrification unit and fluoride adsorption unit on the basis of the existing treatment process, which can provide theoretical support for the selection and upgrading of coal mine water purification process.