Abstract: Aiming at understanding the contribution of drought-resistance to spring wheat yield, we conducted a field experiment with 7 new cultivars(lines) cultivated in arid farmland, to study the physiological characteristics in flag leaf following anthesis and yield components.The result showed that the superoxide dismutase(SOD) activity decreased in flag leaf among different spring wheat cultivars at 21 d after anthesis, with an average decrease of 24.1% compared with that at 14 d after anthesis.Compared with the control of Xihan No.2, the SOD activity in flag leaf of Ganchun No.25 at 7 d, 14 d, 21 d and 28 d after anthesis, increased by 2.3%, 5.0%, 3.0% and 2.3% respectively.With plant growth and development, the malondialdehyde(MDA) content in flag leaf following anthesis gradually increased, and the line 07001-2-5 increased by 31.2% at 28 d after anthesis, which was significantly higher than that at 21 d after anthesis.However, the trends of soluble protein and MDA content in flag leaf after anthesis was reverse, and the soluble protein in cultivar Ganchun 25 at 28 d after anthesis increased by 10.7%~44.1% compared with that of other spring wheat cultivars.In terms of yield components, the spike length in line 06044-3-7-12 increased by 9.2% than that of the control; the spikelet number, grain number per spike and 1000-grain weight in Ganchun No.25 showed the highest value, with 12.8%, 32% and 22.6% higher than that of Xihan 2, respectively.As for grain yield, Ganchun 25 was the highest, followed by strain 06044-3-7-12; their yields were 6.2% and 3.2% higher than that of Xihan No.2, respectively.Therefore, the Ganchun No.25 could maintain a relatively superior physiological status and strong metabolic function, which contributed an increase of 2.9%~29.4% to spring wheat yield than other cultivars.