In this study, the heavy metal contaminated soils were prepared by adding a certain amount of copper, nickel and cadmium salts. The bentonite and tetraethylenepentamine modified bentonite (amino-bentonite) were added to the prepared soils as repair agents, and then available heavy metals were extracted by simulated acid rain and mixed extractant. The extraction rate of heavy metals in each contaminated soil was below 0.1% by simulated acid rain with pH of 3.5. The extraction capability of the mixed extractant for the available heavy metals in the contaminated soil was much stronger than that of the simulated acid rain. Adding bentonite and amino-bentonite could passivate copper, nickel and cadmium in soils. The amino-bentonite had stronger passivation capability for copper, nickel and cadmium than bentonite, because there was complexation between the grafted amino group on the amino-bentonite and the metals. The comprehensive evaluation shows that amino-bentonite is a passivation material with application prospects for copper, nickel and cadmium contaminated soils.