Abstract: Cellulose polyethylenamine is prepared from straw cellulose made by alkalization,epoxidation and enamine.The influencing factors of cellulose polyethylenamine,such as temperature,reaction time,alkali concentration,dosage of epichlorohydrin and diethylenetriamine are all studied.The suitable conditions for epoxidation are as followings.Reaction temperature is 40℃,mass ratio of epichlorohydrin to cellulose is 5∶1,alkali concentration is 8%,and reaction time is 15h.The optimal conditions is temperature 50℃,mass ratio of diethylenetriamine to epoxidation cellulose 1∶1,and reaction time 8h.Cr(Ⅵ) adsorption efficiencies of the cellulose polyethylenamine made under the optimized synthesis condition is 91.1%.