Abstract: An anionic polyelectrolyte P(AM-co-AAK) was synthesized by inverse emulsion polymerization, in which acrylamide (AM) and potassium acrylate (AAK) were used as monomers. The structure and morphology of the product were characterized, and the salt-resistance of the product was studied. Furthermore, the effects on the flocculation performance were investigated in Kaolin suspension simulated wastewater(w=0.1%), including: intrinsic viscosity, product dosage and pH value of system. Results show that the product has good salt-resistance. When the intrinsic viscosity is 6.6 dL/g and the dosage of flocculant is 3 mg/L in the simulated wastewaters, the flocculation performance is the best and the transmittance reaches the highest value (54.43%). The flocculation effect in the alkaline condition is better than that in the acid condition.