Polystyrene-based chelating resins containing amine groups were prepared by chloromethylation of cross-linked polystyrene with chloromethyl methyl ether and SnCl₄ catalysts followed by the reaction with amines such as ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine. Graft-copolymeric chelating resin, poly(styrene-g-ethyleneimine) was prepared by the reaction of chloromethylated copolymer with 2-methyl-2-oxazoline, followed by alkali hydrolysis. Carboxymethylated chelating resins were prepared by the reaction of aminated resin with monochloroacetic acid. The adsorption and desorption separation characteristics toward heavy metal ions such as Hg⁺⁺, Cr⁺⁶, Pb⁺⁺ and Cd⁺⁺ and regeneration of the resins were investigated by column chromatography. Aminated chelating resins showed slow adsorption rate but large adsorptivity toward Cr⁺⁶ ion but carboxymethylated chelating resins showed fast adsorption rate but weak adsorptivity toward Cr⁺⁶ ion and this tendency was observed also for Hg⁺⁺ ion with A₃₄, A₄₅ and A₄₅CM resins. It was observed that A₄₅ resin showed excellent selectivity for one ion in the adsorption separation of the mixed ions such as "Cr⁺⁶ and Cd⁺⁺", "Hg⁺⁺ and Pb⁺⁺", and A₃₄ resin showed good selectivity in the mixed ion "Hg⁺⁺ and Cd⁺⁺". The adsorption separation ability towards a heavy metal ion decreased about 40% by the presence of other heavy metal ions, which is contrary with the case of coexistence with Na⁺ or Ca⁺⁺ ions which exhibited no effect. The selective adsorption separation ability could be expressed by the separation constant α, namely distribution coefficient ratio of the mixed ions for each resin. They were 23, 540, and 380 for K_Cr ⁺⁶/K_Cd ⁺⁺, K_Hg ⁺⁺/K_Pb ⁺⁺ and K_Hg ⁺⁺/K_Cd ⁺⁺ respectively. The selective adsorption separation was excellent as the separation constant α was increased. It was also observed that the desorption separation ability of all the resins were excellent and most of adsorbed ions could bedesorbed from the resins to a degree of about 80% by eluting with IN HCl solution at the initial time. Complete recovery of heavy metal ions were observed. The regeneration of chelating resins A₄₅ and A₄₅CM resins showed excellent readsorption separation ability nearly 100%. It was possible to predict the adsorptivity and adsorption separation ability by comparing with the distribution coefficient (K_d of heavy metal ions toward each resin.