To investigate the flocculation characteristics of polyacrylamide (PAM)-grafted chitosan, a series of PAM-grafted chitosan copolymer (Chito-g-PAM1 to Chito-g-PAM4) have been synthesized by ceric ammonium nitrate-induced solution polymerization technique in nitrogen atmosphere. The flocculation characteristics of the polymer samples (PAM, grafted and ungrafted chitosan) were studied by settling test and jar test methods in the colloidal suspensions of kaolin, iron ore, silica, and bentonite powder. It was found that the settling performance of Chito-g-PAM3 is best among the polymer samples. The jar test results indicate that the ungrafted chitosan has better water clarifying performance than both the PAM and grafted chitosan. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 2410-2414, 2009