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Crop planting structure was generally considered to be basic data for assessment of water productivity and agricultural irrigation water management. And the adjustment and spatial distribution of crop planting structure was closely related to the water consumption and the improvement of soil and water environment, especially in large irrigation district of north China. To deal with water resources crisis caused by climate change and intensified human activities in Hetao irrigation district in north China, many watersaving irrigation projects were taken to solve the problems since 1999. In recent years, net water diversion and ground water depth tended to decrease obviously, and the irrigation efficiency of irrigation districts tended to increase which showed good result of water conservation projects. The purpose of this study was to discover the changes of planting structure adjustment, the characteristics of spatial distribution, the effect on agricultural water consumption changes and the response to the distribution of groundwater. A data fusion approach (Enhance spatial and temporal adaptive reflectance fusion model, ESTAFM) was applied to generate synthetic Landsat7 ETM+ data with MODIS and construct the high spatial and temporal NDVI data sets. And major crop types were extracted successfully by spectral matching technique (SMT) in 2015. The positional accuracy of maize, sunflower, wheat and interplanting were 95%, 88%, 91% and 90% respectively and the historical change of total area of different crops was consistent with the statistics data. Using this method, the planting structure of Jiefangzha irrigation area, the second largest irrigation field in Hetao irrigation district, was effectively extracted over the years and its temporal and spatial variation and correlation with the distribution of groundwater depth were acquired. The result showed that the area of maize and wheat was increasing, the sunflower was decreasing firstly and later converted into an upward trend,and the interplanting area was declining year by year. The factor for the changes of crop planting structure mainly attributed to the market demand and national policies. For spatial distribution, sunflower concentrated in the region with severe salinization in shallow groundwater level, on the contrary, the maize, wheat and intercropping concentrated in the region with slight salinization in deeper groundwater level. The spatial distribution of crop planting was not only closely related to water and soil environment but also physiological characteristics of crops. Although net water diverted from Yellow River decreased year by year, the agricultural evapotranspiration showed an upward trend which caused by planting structure, especially the variation of maize. The groundwater depth declined from 1.76m to 2.33m and the water and soil environment was improved which was contributed to the good performance of watersaving projection.