This study was carried out to optimize the zinc (Zn) foliar application for improving mungbean (Vigna radiata (L.) Wilczek) grain yield and its biofortification. The plants were either sprayed with distilled water, or with Zn solution (0.50, 1.0 and 1.5%) using ZnSO 4 .7H 2 O as source while no spray was also taken as control. Zn foliar application improved the seedling growth, morphological and yield parameters, grain yield and grain Zn concentration in mungbean. Among the various foliar treatments, Zn foliar application at 0.5% was the most effective in improving the root system (longer roots with more roots proliferation), seedling growth, chlorophyll contents, yield related paramet ers, and grain yield; while for grain Zn concentration foliar applied Zn at 1% was effective. Zn application at 0.5 and 1% increased the grain yield and grain Zn concentration by 86 – 38% and 78 – 156%, respectively than no application. Thus, Zn may be foliar applied at 0.5 – 1% for harvesting good grain yield and Zn - enriched grains of mungbean