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With the global warming, droughts occurred more frequently than before. Droughts have occurred in all major farming areas in China, and spread all over the country. The wheat production in the western Loess Plateau is obviously affected by drought, flood and water conditions, so it is necessary to study its response characteristics under the background of meteorology and agricultural droughts in order to put forward effective measures to prevent agricultural production from being negatively affected by drought. The DSSAT-CERES-Wheat model was combined to simulate spring wheat at seven sites in the western Loess Plateau. The growth factors and yield data from 1961 to 2018 were collected and their temporal and spatial changes were analyzed. The standardized precipitation evapotranspiration index (SPEI) and soil moisture deficit index (SMDI) at the 0~10cm depth and 10~40cm depth at the time scales of 1~6 months were estimated, and the temporal and spatial changes of meteorological and agricultural drought were explored. The effects of drought severity on the growth process and yield of spring wheat were further studied. The results showed that taking Linxia Station in Gansu as an example, the dry and wet status of SPEI and SMDI at the time scale of 1~6 months were generally consistent, SPEI generally showed alternatively wet and dry conditions, and the changes in SMDI at the 0~10cm depth and SMDI at the 10~40cm depth were basically the same, showing a wetter trend. The DSSAT-CERES-Wheat model was effective in simulating the key growth period and yield of spring wheat in the western Loess Plateau (0.65≤R2≤0.84). The maximum leaf area index of spring wheat from 1961 to 2018 and the above-ground biomass had no obvious change trends, but the yield had an increasing trend after 2005. Drought in the jointing and filling stages had greater impacts on the growth process and yield of spring wheat. The relationship between SMDI and spring wheat growth and yield elements was closer than SPEI, indicating that agricultural drought had a greater impact on winter wheat growth and yield. The 2 month SMDI at the 0~10cm depth was a key time scale for showing the effects of drought on spring wheat growth and yields. The research result provided a useful reference for the prevention of meteorological and agricultural drought in spring wheat production on the western Loess Plateau.