A tin(IV) antimonate(SnSbA) cation exchanger has been synthesized under different conditions; changes in the concentration, the molar ratio of Sb/Sn in the starting solution, and hydrolysis temperature. The products obtained were characterized by powdered X-ray diffraction and thermal analysis, and infrared spectra. The pH titration curves on SnSbA showed apparently mono-basic acid, but can be expected to the presence of the number of the functional groups with overlapping different pKa values. The increased acidities were observed with increasing the molar ratio (Sb/Sn) in the exchanger. The equilibrium distribution coefficients were determined at micro-amount of alkali metal ions in the hydrochloric acid solution. The SnSbA showed an unusual selectivity for alkali metal ions compared to cation exchange resins and other inorganic ion-exchangers.