The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Y? were investigated. The statically saturated adsorption capacity is 102mg· g- 1 resin at 298K in HAc NaAc medium at pH 5.7. Y? adsorbed on IDAAR can be reductively eluted by 1.0~ 4.0mol· L- 1 HCl used as eluant and the elution percentages are almost as high as 100% . The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k298=3.36× 10- 5s- 1. The adsorption behavior of IDAAR for Y? conforms to Freundlich′ s model reasonably. The thermodynamic adsorption parameter, enthalpy change Δ H of IDAAR for Y? is 18.6kJ· mol- 1. The complex molar ratio of the functional group of IDAAR to Y? is about 3∶ 1. The adsorption mechanism of IDAAR for Y? was examined by using chemical method and IR spectrometry.