In this paper, natural starch was used as raw material to synthesize starch based heavy metal trapping materials by stepwise molecular modification, and the trapping ability of copper and nickel ions was evaluated. The starch molecules first introduce cationic quaternary ammonium groups through etherification. On this basis, continue to introduce the phosphorylation of anionic groups. The addition of urea in the synthesis process could promote the cross-linked structure of various types of groups and introduced non ionic groups. Finally, modified starchproducts with multiple charge distribution were obtained. The results showed that the dosage of CHPTAC was 4%（mL/g） of starch quality, reaction temperature was 50℃ for 4h, the degree of cation substitution was 1.61%.The mass concentration of sodium tripolyphosphate was 4%, pH value as 6-7, reaction temperature was 120℃ for 2h, the degree of substitution of negative charged could reach0.026.Low concentration of urea can improve the reaction efficiency of phosphorylated starch. When the mass percentage concentration is higher than 3%, it can enhance the cross-linking of starch with the molecular carbamate. The products with different degree of substitution have a certain trapping effect on the copper and nickel ions. When the cationic and anionic phosphate esterification degree of substitution were 1.421% and 0.018, the removal rate of 30 mg/L copper and nickel ions solution could reach 98%.