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Multiple cropping is an efficient way to improve the crop yield for Guanzhong area of Chinese Loess Plateau. The spatiotemporal pattern change of multiple cropping in Guanzhong area from 2000 to 2013 was investigated. Cropping index was employed to quantitatively assess the multiple cropping. The twi-difference algorithm was applied to estimate the cropping index based on the crop NDVI time-series reconstructed from 250m 16d MODIS NDVI datasets with the iterative Savitzky-Golay method. Results were as follows: the cropping index was shown to be the highest in Xi’an City and it was decreased with the increase of distance from the city;the croplands with double seasons were mainly located in the Weihe River plain with an altitude of less than 600m;the single-season croplands were primarily distributed over the loess ravine regions of the northern Guanzhong area, Qinling mountain area of the southern Guanzhong area and alluvial plain along the Yellow River (eastern Guanzhong area). The cropping index in 2000—2013 was found to reveal a two-stage downward trend. During 2000—2005, the cropping index was reduced very slowly and the rate of the decline was less than 2%;however, the decrease rate became high during 2006—2013 which reached 15.7% in 2013. The development of urbanization and economical agriculture were demonstrated to significantly influence the decline of cropping index. Through the comparison with the statistics issued by the government, the average relative error of cropping index estimated from MODIS datasets was between 0.3% and 15.1% at the regional level, and the result also had an accuracy of 93.7% at the pixel level. The presented results provided useful and reliable information for the decision making on spatially-targeted local agricultural planning.