Abstract: To recover aluminum and iron from red mud and, simultaneously, prevent the environment pollution and occupancy of large-area land from the recovery, the polyaluminium ferric chloride(PAFC) was prepared with red mud, to treat the kaolin-containing wastewater. A contrast test was carried out with PAFC and PAC(polyaluminium chloride) both used as flocculants to investigate the effects of the dose of flocculants, the pH value, concentration and temperature of wastewater, and basicity on flocculation. The results indicated that all the influencing factors as above except the wastewater temperature affect the flocculation greatly. The maximum depollution rate by PAC is 93%, while that by PAFC comes up to 96%.