Chemical modification of natural zeolite (NZ) originated from the Vranjska Banja deposit has been performed with the aqueous solution of Fe(NO3)3 at pH=3.6 and with NaOH and NaNO3 solutions. Fe(III)-modified zeolite (FeZ) has shown 3-4 times higher capacity towards cadmium and zinc compare to the natural zeolite. The modification did not cause changes in the structure and mineralogical composition, but it increased the pore volume and the amount of sodium as a result of ion exchange and neutralization of the negative charge created during the modification. The increased sodium content is responsible for the higher removal capacity of FeZ toward zinc and cadmium. The effect of pH and concentration of the metal ions solution, the particle size and the mass of zeolite expressed by S/L ratio (solid/liquid), and the contact time of zeolite-solution, on zinc and cadmium removal on NZ and FeZ have been investigated. Equilibrium results for different concentrations of Zn and Cd and two particle sizes of NZ and FeZ have been tested according to the isothermal models: Langmuir, Freundlich, Temkin, Sips, Toth, DubininRadeuskevich and Hill. The dimensional analysis has been applied and equilibrium parameters which are independent of S/L ratio and the initial concentrations have been obtained. Kinetic results were tested according to the reaction kinetic model (Lagergren's pseudo-first-order and Ho's pseudo-second-order) and diffusion kinetic models (Doubleexponential, Weber-Morris, Bangham, Vermeulen's approximation and diffusion through the laminar film). It has been found that the diffusion through the particle is the rate limiting step of process. The model curves for metal ions uptake per gram of zeolite vs. time were obtained from the calculated parameters of the models. It has been found that the Double-exponential model and Vermeulen's approximation fit throughout the whole examinated time interval. Hence, these models have been selected for predicting the quantity of zinc and cadmium uptake at chosen time and at chosen initial concentration. The investigation of desorption of zinc and cadmium from saturated modified zeolites in ultrapure water of different initial pH has shown that saturated zeolites do not release zinc and cadmium, while they are released in NaCl, KCl and NaNO3 solutions. During four consecutive cycles of saturation and regeneration of the same FeZ mass the capacity remained unchanged, indicating excellent sorption-regeneration properties of FeZ.