Extraction of Eu(III) from wastewater has recently received extensive attention in environmental water pollution improvement because Eu(III) is the chemical analogue of trivalent lanthanides [Ln(III)] and actinides [An(III)]. In this work, UiO-66-AO with remarkable physicochemical properties was designed through introducing amidoxime groups (C(NOH)NH2) on the surface of UiO-66-CN which was derived from UiO-66-Br through introducing cyano groups (C N). SEM, TEM, BET, FT-IR, XRD, and TGA techniques demonstrated the effective synthesis and excellent structural performances of target materials. The outstanding sorption efficiency of UiO-66-AO (similar to 253.8 mg/g within 2 h) was verified through kinetic and thermodynamic analyses, showing that the kinetics data were well fitted by pseudo-second-order kinetic model, and the sorption isotherms were effectively fitted by Langmuir model. Based on macroscopic experiments and spectroscopic analyses (FT-IR and XPS), the removal mechanisms of Eu(III) onto UiO-66-AO were electrostatic interaction and inner-sphere surface complexation. In addition, the environmental application assessment had proved that UiO-66-AO owned excellent stability, outstanding selectivity, and remarkable Eu(III) removal percentage in simulated wastewater systems, demonstrating the great potential of UiO-66-AO to remove radionuclides from the actual wastewater.