Abstract:The effects of drip system uniformity and irrigation amount on the crop water stress index (CWSI) were evaluated in arid environments of Xinjiang Uygur Autonomous Region, China, during the growing season of cotton in 2011 to amend the current design and evaluation standards of drip system uniformity. Three Christiansen uniformity coefficients (C_u) of 0.65, 0.78, and 0.94 and three irrigation levels of 50%, 75%, and 100% of full irrigation were used. A higher irrigation amount resulted in a lower canopy temperature and CWSI. The uniformity coefficients of canopy temperature and CWSI, which ranged from 0.91 to 0.98 and 0.65 to 0.91, respectively, were positively correlated with the drip system uniformity. Irrigation amount had a significant effect on canopy temperature and CWSI at the 0.01 level. The influence of drip system uniformity on the uniformity coefficient of canopy temperature and CWSI were significant at the 0.05 or 0.01 level. A significantly negative correlation between lint yield and CWSI was observed. The reduction of lint yield caused by water stress for the low uniformity treatment was lower than that for the high uniformity treatment.