Abstract: The industrial residue corncob lignin(CL) was used as raw material and activated by phosphoric acid, potassium hydroxide, and zinc chloride, respectively, to obtain lignin-based carbon materials, PA-CL, PH-CL and ZC-CL.And the carbon materials were used for adsorbing the chromium(Cr(Ⅵ)) ions from wastewater. Results showed that phosphoric acid activation process was simple, environmentally friendly and the activation temperature was low. And the phosphoric acid activated sample had higher adsorption efficiency for Cr(Ⅵ) than NaOH and Zncl₂ activated samples. The removal efficiency of Cr(Ⅵ) by using PA-CL reached 79.2% in the first 5 min and 96.5% in 40 min with the initial Cr(Ⅵ) mass concentration 50 mg/L and adsorbent dosage 0.05 g at 50℃. The structural features of carbon material were analyzed by FT-IR and SEM and the functional groups on the surface of carbon materials were tested by the Boehm titration. The results showed that the phosphate group was introduced onto the surface of PA-CL and the total acidity increased to 3.20 mmol/g from 2.54mmol/g(original lignin), which was beneficial to adsorption of Cr(Ⅵ). The adsorption was described well with the pseudo-second-order model with q_e of 390.6 mg/g and R² of 0.991 0, for PA-CL. And the adsorption isotherm conformed to the Langmuir model with R²>0.9, which indicated that the adsorption of Cr(Ⅵ) on PA-CL was chemical adsorption-based monolayer adsorption.