This experiment was carried out to examine the effect of water stress at anthesis on the grain maturation and to interpret the immediate and resulting growth response in barley. The dry weight of root, stem, internode, flag leaf and grain under water stress was remarkably more reduced than that under no-water stress, respectively. Water stressed plants had heavier grain dry weight during 7.14 days after water stress than that under no-water stress, but this early response was reversed significantly in the later period. The relative turgidity of organs except grain under water stress was severely lowered than that under no-water stress. The net photosynthsis by rewatering after water stress had been kept at the lower level than that under no-water stress ti1l the late maturation.