The wastewater of Cr~(6+) was investigated by corncob.The results indicated corncob powder are a good kind of sorbent of Cr~(6+).The activated corncob power has more strong adsorption about Cr~(6+) than natural corncob power. At a pH value of 1 and residence time of 2 h,the adsorption rate of Cr~(6+) by The activated corncob power can achieve over 83 %.