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Perennial ryegrass (Lotium perenne L. cv. 'Grasslands Ruanui') plants were grown in a sulphur-responsive soil in a glasshouse with five rates of fertiliser nitrogen (N) Ca (N0 3 ) 2.4H 2 0) and three rates of sulphur (S) (CaS04.2H 2 0). Compared with control, N fertilisation significantly increased sodium (Na) concentration in both tops and roots, but decreased potassium (K) concentration. However, S fertilisation increased K but decreased Na content of tops only at low N levels. The effect on roots was not consistent. Increasing N applied generally decreased the sum of inorganic anions (~A = CI-+ N0 3 -+ H 2 P0 4 -+ S04 2 -), mainly due to decreases in CI-, S04 2 ", and H 2 P0 4 -concentrations. Nitrate concentration increased with N applications and showed an inverse relationship to cr concentration in plant tops. The organic acid content (C -A) of herbage was not directly related to levels of N applied. Nitrogen fertilisation decreased the cation/anion ratios and S applications increased the ratios. The EB/N ratios were als0 decreased by N fertilisation, and S fertilisation, particularly at low N levels, increased EB/N ratios.