Cauliflower (Brassica oleracea L. var. botrytis) plants subjected to Zn defíciency showed decreased leaf water potential and transpiration rate, and increased leaf thickness, and accumulation of sugars and starch. Zn-deficient leaves also showed decreased photosynthetic rates (P^) and compensation irradiance and increased apparent quantum efficiency. Decrease in leaf chlorophyll (Chl) content due to Zn defíciency, though signifícant on fresh mass unit was insignifícant on leaf area unit. Decreased was not attributable to the effects of Zn defíciency on Chl content upto 51 d of treatment. Zn-defícient leaves showed an insignifícant decrease in photosynthetic O2 evolution at saturating irradiance and CO2 supply; signifícant decreases in P^, stomatal conductance and intercellular CO2 concentration when the leaves were supplied with CO2 at atmospheric concentration suggest that stomatal limitation contributes signifícantly towards decreased P^ in Zn-defícient leaves.