Copper slag based chemically bonded ceramics (CSCBC) prepared through the alkali activation of copper slag was used to adsorb Cr(Ⅵ) ions in the waste water. The influence of the addition amount of adsorbent, initial concentration of Cr(Ⅵ) and pH on the adsorption efficiency was investigated, and the adsorption mechanism was discussed by the adsorption kinetics and thermodynamics analysis and characterization of adsorbent before and after adsorption. The result showed that the adsorption equilibrium can be reached within 120min, the removal rate was up to 93% and the maximum theoretical adsorption capacity was 25.3mg/g at the optimal condition (adsorbent addition amount: 0.4g, initial concentration of Cr(Ⅵ): 100 mg/L, pH: 1.0) . CSCBC has higher adsorption capacity than the same type adsorbents such as biochar-based iron oxide composites, FeS composite and Cr(Ⅵ)able metal ion doped adsorbent. The adsorption process of Cr(Ⅵ) by CSCBC was in accordance with the quasi-first order kinetic model and Langmuir isotherm adsorption model. The adsorption mechanism can be explained from two aspects of reduction and physical adsorption. The adsorption capacity remained 75% of the initial adsorption capacity after 6 adsorption-desorption experiments.