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Studying the phenophase of crops is an important way to identify crop planting patterns and extract crop areas. It is also of great value for crop growth monitoring and yield assessment. Based on the ESTARFM model, the MODIS and Landsat image data of the Xiong'an New Area in 2006-2010 are combined to make the data have high spatial and temporal resolution advantages. The Savitzky-Golay (SG) filtering method and the dynamic threshold method are used to perform NDVI on the obtained fusion data set. The time series data was reconstructed, and the key phenophase of winter wheat and summer corn in Xiong'an New Area was compared with the local actual crop planting system. The results show that: (1) Before using Savitzky-Golay filtering method, the NDVI time series is not well-formed, and there is more noise information. After smoothing with Savitzky-Golay filter, the NDVI time series curve can maintain the original curve shape. On the basis of this, the irregular fluctuation of the original data is eliminated, and the details of the curve are well preserved. At the same time, the curve exhibits a distinct bimodal morphology and also conforms to the growth characteristics of winter wheat and summer corn. (2)Through years of research data, it is known that the winter wheat returning green period is usually in the middle of March, the heading period is generally in early May and mid-May and the mature period is mostly in early June and mid-June. The summer corn seeding period is generally in mid-June, the jointing period is in mid-July, the tasseling period is mid-August and late August, the mature period is generally mid-October. Comparing the actual crop planting system in Huang Huai Hai plain, the identification and extraction results of winter wheat and summer corn phenological information are consistent with the practical situation, it may provide a scientific basis for the transformation of agricultural industry in Xiong'an New Area.