Abstract: A spherical composite adsorbent of ferrocyanide nickel potassium binding with polyacrylonitrile(KNiFC/PAN) was prepared. The KNiFC/PAN was characterized and analyzed by XRD, metalloscope, ICP-MS, etc. Cs⁺ adsorption on KNiFC/PAN as a function of the concentrations of nitric acid, Na⁺, NH⁺₄, and contact time was studied through batch experiments. Furthermore, the adsorption kinetics and isotherms were analyzed. The results show that the typical adsorption distribution coefficient(K_d) for Cs⁺ is 10⁴-10⁵ mL/g, and the adsorption equilibrium time is within 5 min. When the concentration of nitric acid is less than 1.0 mol/L, the K_d value is almost unaffected, and the K_d value decreases with acid concentration increasing while the concentration of nitric acid is greater than 1.0 mol/L. And Na⁺ has a little effect on adsorption of Cs⁺, however, NH⁺₄ has significantly competition with Cs⁺. The adsorption isotherm of Cs⁺ on the adsorbent is better described with the Langmuir equation model, and its saturated adsorption capacity is 127 mg/g, the pseudo-second-order kinetics equation fits well with the experimental data. Finally, it is proved by column experiments that the adsorbent can remove ¹³⁷Cs to less than 10 Bq/L, and with more than 17 500 volume reduction factors. The adsorbent is easy to using for column operation and hopeful for deep purification of radioactive low level water in nuclear field.