An oxidized starch with carboxyl groups was prepared by oxidizing corn starch.The results of orthogonal experiments indicated that absorptions of oxidized starch and corn starch to Cr(VI) were influenced by pH,temperature,reactive time and the amount of absorption reagents.The order of influence for corn starch was pH,temperature,the amount of corn starch as absorption reagent and reactive time;the order of influence for oxidized starch was pH,reactive time,temperature and the amount of oxidized starch as absorption reagent.The difference in the two orders may be resulted from the presence of carboxyl groups.The experiments also indicated that the absorption of oxidized starch to Cr(VI) was better than that of corn starch.