Drought is a natural hazard that arises from climate fluctuations and variations. It frequently triggers negative impacts on economies

societies

and environments. This paper presents a new remote sensing-based drought index called the MODIS Shortwave Infrared Water Stress Index（ MSIWSI） for monitoring agricultural drought. Changes in the water content of plant tissues or soil have a large effect on the reflectance in several regions of the shortwave infrared spectrum. MSIWSI integrates relevant information from the shortwave infrared channels 6 and 7 from the MODIS satellite data based on the distribution of different land cover classes in the MODIS shortwave infrared spectral feature space. Correlation and regression analyses are performed on MSIWSI and two other well-known drought indexes—the Enhanced Vegetation Index（ EVI） and Modified Perpendicular Drought Index（ MPDI） —and on ground-measured soil moisture data to assess the capability of MSIWSI in arid regions in northwest China. Pearson correlation analyses were also performed on MSIWSI and ground-measured soil moisture data of spring wheat during different phonological phases. Results show that MSIWSI performed better than EVI and MPDI in soil moisture retrieval. MSIWSI can also reflect the probable soil moisture trends of spring wheat. This investigation indicates that MSIWSI has significant application potential in monitoring agricultural drought in arid regions.