Abstract: There are many factors affecting sorghum high-yield, such as variety, water and fertilizer, soil and climate, etc. To explore high-yield performance of sorghum and look for the research breakthrough of sorghum yield influencing factors, the maximum water requirement on the stage of sorghum jointing and flowering and lifelong water consumption characteristics of grain sorghum were studied by the method of univariate randomized complete block design. The results showed that water consumption and ear length and branch number increased significantly as the quantity of irrigation water increased, no significant difference was found on the ear length and branch number by the 120-140 mm irrigation amount. 1000-grain weight and yield of grain increased significantly, no obvious difference was found by the 100- 140 mm irrigation amount. The conclusions showed that the maximum water requirement was 120 mm for sorghum jointing stage and 100 mm for flowering filling stage. Water consumption was 48.74 mm before sorghum jointing stage, which accounted for 10%-15% of the total water consumption. Water consumption was 140.51-177.12 mm from jointing to heading, which accounted for 35%- 43% of the total water consumption. Water requirement was 137.65- 272.27 mm from heading to maturation, which accounted for 42%-55% of the total water consumption. There was a trend that water productivity increased first and then decreased with the increasing of water consumption. Water productivity was the highest on the sorghum filling stage by the treatment of the 100 mm irrigation amount, which could reach 29.49 kg/(hm²·mm).