Abstract: In order to solve the problem of high turbidity in the mine water of Baorixile open-pit mine, the electrochemical characteristics of the mine water were analyzed, the particle size of the suspended solid particles was mainly distributed between 0.6 μm and 0.8 μm, and the Zeta potential was between -23 mV and -25 mV, the positively charged coagulant should be selected for settlement. On this basis, the "PAC + PAM" combined treatment process was optimized. The results shows that when the combined addition method of coagulants of 30 mg/L PAC + 0.5 mg/L PAM is adopted, the effluent turbidity is the lowest, reaching 10.8 NTU, the removal rate reaches 95.5%; under the condition of single addition, PAC and PAFC are better than PFS in removing turbidity in water, but the removal effect of COD_cr in water is not as good as PFS, and the addition of three flocculants can not effectively reduce the total hardness of water.