In our research, a type of cyclodextrin-based polycarboxylic acid polymer (BTCA-β-CD) was prepared by cross-linking β-cyclodextrin (β-CD) and 1,2,3,4-butanetetracarboxylic acid (BTCA) with a green and facile methods, and the adsorption performance of radionuclides such as U(VI) and Eu(III) were systematically studied through batch testing. The results revealed that the obtained maximum adsorption values of BTCA-β-CD for U(VI) and Eu(III) ions were 175.6 and 165.4 mg/g, respectively. The adsorption kinetics on both adsorbents followed pseudo-second-order model. A plausible adsorption mechanism was explored by related characterization, verifying the carboxyl and hydroxyl groups of the polymer work together as adsorption sites. [ABSTRACT FROM AUTHOR]