Abstract <p>Specific features of the chromatographic retention of alkali and alkaline-earth metal cations on poly(styrene–divinylbenzene) cation-exchangers functionalized with carboxyl groups are considered. It was found that the retention of metal cations of equal charges correlates directly with their polarizability. The effects of eluent type and concentration on the retention of metal and ammonium cations were studied and the contributions of secondary processes to the retention and peak shape were evaluated. An increase in the eluent concentration improved the symmetry of the chromatographic peaks. Van’t Hoff plots were constricted and adsorption enthalpies (Δ<i>H</i>°) were estimated. Column efficiency increased with temperature. A possibility of the simultaneous determination of alkali and alkaline-earth metal ions and ammonium cations on carboxylic cation-exchangers with either direct or suppressed conductometric detection was demonstrated. The applications of these adsorbents to water analysis are discussed.</p>