Abstract: It is essential for optimizing the use of agricultural water resources and improving agricultural production efficiency to quantitative assessment of long-term trends in Crop Water Use Efficiency (CWUE). Taken three typical crops (cotton, maize and winter wheat) of the oasis agricultural area of the Manas River Basin on the Northern Tianshan Mountains in Xinjiang as the research objects, based on the long-term agricultural meteorological observation data of the Wulanwusu Agricultural Meteorological Station in the basin from 1980 to 2023, this study clarified the long-term trends of CWUE of the three typical crops by using correlation analysis, trend analysis and geographic detector statistical methods, and analyzed the contribution rate of meteorological factors and management measures to CWUE. The results show that in the past 44 years, the unit yield of the three typical crops in the basin have shown an increasing trend, and the evapotranspiration has increased first and then decreased, The change of CWUE is from a non-significant change to a rapid improvement. The CWUE of the cotton and maize increase the most significantly in mulching film and drip irrigation(LD) stage(the annual growth rates are 0.022kg·m^-3·a^-1, 0.281kg·m^-3·a^-1, respectively), and the CWUE of winter wheat increase the most in the non-film and drip irrigation(ND) stage (the annual growth rate is 0.094kg·m^-3·a^-1). The effect of management measures on CWUE is more than that of meteorological factors, and the contribution rates of CWUE to cotton, corn and winter wheat are 63.02%, 61.75% and 58.86%, respectively. Among the meteorological factors, the CWUE of cotton is mainly affected by Accumulated Temperature Above 0℃, while the Sunshine Duration contribute more to the CWUE of corn and winter wheat. This study will provide a scientific data support for the efficient utilization of agricultural water resources and food security in the Northern Tianshan Mountains.