Abstract: A novel flocculant based on PAM-Fe(OH)3 hybrid was synthesized with a redox initiation system composed of (NH4)2S2O8-NaHSO3. The effects on intrinsic viscosity of PAM-Fe(OH)3 hybrid were studied using orthogonal test method. Results showed that the optimum reaction conditions were as follows: temperature 40 °C, mass fraction of initiator 0.5%, reaction time 7 h, the monomer mass fraction, 30%. PAMFe(OH)3 hybrid was characterized by FT-IR spectroscopy, TGA, and conductivity measurement. An ionic bond existed between Fe(OH)3 colloid and polyacrylamide(PAM) chains in the hybrid. Flocculation studies showed that the optimal dosage was 40 mg/L and the hybrid flocculant was superior to polyferric sulfate(PFS) or PAM.