In this study,three magnetic flocculants with different chelating groups,namely,car-boxymethyl chitosan-modified Fe3O4 flocculant(MC),acrylamide-grafted magnetic car-boxymethyl chitosan flocculant(MCM),and 2-acrylamide-2-methylpropanesulfonic acid copolyacrylamide-grafted magnetic carboxymethyl chitosan flocculant(MCAA)were pre-pared,synthesized,and characterized by photopolymerization technology.They were ap-plied to the flocculation removal of Cr(Ⅲ),Co(Ⅱ),and Pb(Ⅱ).The effect of flocculation con-dition on the removal performance of Cr(Ⅲ),Co(Ⅱ),and Pb(Ⅱ)was studied.Characterization results show that the three magnetic carboxymethyl chitosan-based flocculants have been successfully prepared with good magnetic induction properties.Flocculation results show that the removal rates of MC,MCM,and MCAA on Cr(Ⅲ)are 51.79％,82.33％,and 91.42％,re-spectively,under the conditions of 80 mg/L flocculant,pH value of 6,reaction time of 1.5 hr,G value of 200 s-1,and precipitation magnetic field strength of 120 mT.The removal rates of Co(Ⅱ)by MC,MCM,and MCAA are 54.33％,84.99％,and 90.49％,respectively.The removal rates of Pb(Ⅱ)by MC,MCM,and MCAA are 61.54％,91.32％,and 95.74％,respectively.MCAA shows good flocculation performance in composite heavy metal-simulated wastewater.The mag-netic carboxymethyl chitosan-based flocculant shows excellent flocculation performance in removing soluble heavy metals.This research provides guidance and ideas for the develop-ment of efficient and low-cost flocculation technology to remove heavy metals in wastew-ater.