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In order to promote the sustainable development of agriculture and ecological environment in the Loess Plateau, based on MODIS evapotranspiration products and meteorological station data from 2001 to 2020, the characteristics of drought change and its influencing factors in the Loess Plateau were discussed by using crop water stress index ( CWSI), Theil-Sen Median trend analysis, Mann-Kendall test and partial correlation analysis. The results show these as follows. Interannually, the CWSI of the Loess Plateau showed a significant linear decline process from 2001 to 2020, and the decline rate was 0. 0058 ·a -1 (P < 0. 01). The degree of drought decreased first (2001—2018) and then increased (2018—2020). Spatially, the CWSI was dominated by a decreasing trend, with a significant decreasing trend accounting for 91. 24% of the total area of the region. Among them, the CWSI in Qinghai, Gansu, Ningxia and southern Shaanxi decreased faster. The negative partial correlation between CWSI and temperature was dominant in the Loess Plateau, and the significant negative partial correlation accounted for 7. 78% of the regional area, which was concentrated in the eastern Qinghai, southern Shanxi and northern Henan. There is a negative partial correlation with precipitation, which accounts for 60. 88% of the total area and is concentrated in the southwest and east of the Loess Plateau. Under the background of rising temperature, the increase of precipitation promoted the significant increase of ET(evapotranspiration) and insignificant decrease of PET(potential evapotranspiration) in the Loess Plateau, resulting in a significant decrease of CWSI. It is concluded that precipitation is the main factor affecting the decrease of CWSI in the Loess Plateau, and the significant increase of annual precipitation slows down the drought trend in the Loess Plateau. [ABSTRACT FROM AUTHOR]