Waste polystyrene plastic as raw material was reacted with chlorine methyl polystyrene, then reacted again with the iminodiacetic acid, an environment-protecting amino acid type chelating resin was prepared. The structure of resin was characterized by IR and thermal analysis represents. The adsorption capacity of resin was measured by Atomic Absorption Spectrometer. The results showed that the resin could adsorpt Cr3+, Pb2+ well. The mechanism of adsorption conforms to Langmuir. Moreover, it can achieve adsorption balance within 30min, the adsorption quantity respectively reached 2.17 mmol/g and 2.11mmol/g at 318K.