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Long-lived radionuclides such as 60Co and 54Mn in radioactive waste water must be properly treated to protect the environment from long-term radioactive hazard. In this study, nine zeolite imidazole frameworks (ZIFs) were initially synthesized to investigate an effective adsorbent for Co­(II) and Mn­(II) in solution. Zeolite imidazole framework-14 (ZIF-14) with good performance was selected, and subsequent characterization and adsorption performance tests were conducted. The results show that ZIF-14 has good hydrothermal stability within 520 °C. Under the conditions of pH = 6.72, T = 303 K and the initial concentration of 500 mg·L–1, the saturated adsorption capacity for Co­(II) and Mn­(II) reached 148.55 mg·g–1 and 252.85 mg·g–1, respectively. The analysis of thermodynamic parameters shows that the adsorption process of ZIF-14 to Co­(II) and Mn­(II) is spontaneous and endothermic. The pseudo-second-order kinetic model, Langmuir isotherm model, and Boyd model are more in line with the adsorption process of Co­(II) and Mn­(II) by ZIF-14, which proves that the active sites on the surface of ZIF-14 are evenly distributed, and the adsorption process is single-molecule chemical layer adsorption. In addition, the liquid film diffusion dominates the adsorption rate during the adsorption process of Co­(II) and Mn­(II) by ZIF-14. ZIF-14 has good selectivity for cobalt and manganese in both high-concentration interference ion solution and multimetal ion solution with the same concentration. Moreover, ZIF-14 still has good adsorption performance after five times of elution.