Photosynthetic rate, total dry matter, pod yield and harvest index were assessed for 20 cultivars of green gram (Vigna radiata (L.) Wilczek) in field studies. Photosynthetic rates were measured at different growth stages. Correlations were worked out between leaf photosynthesis and pod yield, total dry matter and harvest index, for each stage. Significant cultivar differences were observed in all parameters studied. At the early pod development stage, a positive and significant correlation existed between leaf photosynthesis and total dry matter, pod yield and harvest index. Leaf photosynthesis increased with advancing age and high photosynthetic rates were evident at the flowering stage, with decline thereafter. Correlation studies indicated that a high photosynthetic rate at the early pod development stage could increase seed yield if high dry matter and harvest index are ensured at this stage. Mean leaf photosynthesis over stages showed significant correlation with pod yield (r = 0.54, P < 0.05).