Abstract: In view of the traditional flocculants used in the pretreatment process of high turbidity mine water,there are problems such as low efficiency,large dosage,and difficulty in removing turbidity and emulsified oil. Inorganic-organic composite flocculants was used to coagulation and sedimentation treatment of mine water  to achieve the goals of high efficiency,environmental protection and greenness. The effect of flocculant on the removal of turbidity and emulsified oil under different dosage,temperature and pH conditions was studied through indoor simulation test. The results show that the removal effect of composite flocculant (PFS-P) is better than that of polyferric sulfate (PFS) and cationic polymer P(AM-DMDAAC-OM). When the dosage is 60-75 mg/L,the temperature is 20 ℃,and the pH=7,the removal effect is the best. The removal rate of turbidity reaches 99.3%-99.7%,and the remaining turbidity is only 3.1-7.4 NTU. The removal rate of emulsified oil is about 75.24%,and the remaining oil content is 7.0 mg/L. The analysis results of FT-IR,XRD and TEM show that the inorganic and organic flocculants are effectively combined. The ionic bond in AM interacts with the SO2-4 bond of PFS to connect,and the composite flocculant finally presents a network structure under the action of the adsorption bridging. Under the action of Fe(Ⅲ) hydroxyl complex,long-chain organic molecule adsorption and neutralization,and net trapping and sweeping action of composite flocculant,it can effectively remove turbidity and oil in water. The preparation of composite flocculants and their simulated wastewater treatment tests provide theoretical references for the engineering application of coagulation and sedimentation treatment of high turbidity mine water.