A experimental study on the adsorption effect of Na-bentonite to Cu2 and Cd2 coexisting in solution was carried out under different conditions such as shaking time,the concentration of Cu2 / Cd2 ,the granularity of mineral and the pH of solution.And the abilities of Na-bentonite to Cu2 or Cd2 coexisting in a solution had been compared with one to Cu2 and Cd2 singly existing in a solution.The results showed that the adsorption characteristics of Na-bentonite to the concomitant Cu2 and Cd2 are consistent with one to singly-existed Cu2 and Cd2 ,the higher pH is helpful to the adsorption of Na-bentonite to them.The adsorption effect of Na-bentonite with different granularities to concomitant Cu2 and Cd2 is also consistent with singly-existed Cu2 and Cd2 ,but when the grain size of Na-bentonite is finer(500 and 1000 mesh) the adsorption quantity of Cd2 coexisting in solution with Cu2 is more than one of Cd2 singly-existing in solution;the adsorption effect of Na-bentonite to the Cu2 and Cd2 coexisting in solution was same with their singly-existing in solution,as the adsorption of Cu2 and Cd2 on Na-bentonite surface is in different place.