Abstract:The agricultural and physiological efficiencies of nitrogen applied at different stages of a good quality wheat were studied. Results indicated that the agricultural and physiological efficiencies of nitrogen applied at early elongation stage were higher than those of nitrogen applied as basal in incresing whole grain protein and storage protein. The nitrogen fertilizer applied at elongation stage increased not only the quantity but also the quality of grain protein. While the nitrogen applied at tillering stage increased the quantity of protein but the quality of protein decreased.