Abstract: Acrylamide (AM)-(2-methacryloyloxyethyl)trimethyl ammonium chloride (DMC)-(acryloyloxyethyl)trimethyl ammonium chloride (DAC) copolymers with high cationic monomer content were synthesized. Effects of the initiator, monomers, chain transfer agent concentration and polymerization pH on the molecular weight of the products were investigated. Results indicate that the obtained products have intrinsic viscosity higher than 36 dL/g, good dissolubility, high cationic degree and flocculation performance.