Exchang-eadsorption of aluminum and manganousions by red soils continued being studied.It was shown that the nonelectrical adsorption of aluminum and manganousions was related to either adsorption capacity of solid phase or adsorption intensity of ion;For the ion exchange reaction in soils,it seemed impossible to obtain equilibrium constant k;K and 1/n were also not fixed values;The change in standard free energy ΔG^o of exchange-adsorption between aluminum and potasium was greater than that between it and calcium,it was also the greatest in laterite system.Changes in k,K,1/n and ΔG^o were affected both by the property of solid phase surface and by the nature of ion itself.