A field experiment on an alkali soil (ESP 94) studied the effect of gypsum applied at 0, 2·5, 5 and 10t/ha and zinc sulphate applied at 0, 10, 20, 30 and 40 kg/ha on the growth, yield and chemical composition of rice. The effects of gypsum and zinc applications were additive. Optimum response of rice was to 10 kg zinc sulphate/ha at the 5 and 10 t/ha gypsum levels. At low levels of gypsum, plant growth was poor owing to toxicity of Na and/or deficiency of Ca, and higher levels of zinc sulphate gave a yield response. Zinc-deficient plants had significantly lower Zn concentration but higher concentrations of Fe, Mn, Cu, Ca and Mg than the healthy plants. Application of gypsum decreased the concentration of Na, Fe and Zn in rice plants and increased the concentration of Ca, K, Mn and Cu. in plots not treated with gypsum, the Zn concentration of plants was higher but grain yield was lower than that of gypsum-treated plots. Application of zinc increased the DTPA-extractable Zn but gypsum decreased the soil sodicity and DTPA-extractable Zn in alkali soils.