Taking winter wheat in China as an example, large-scale crop planting areas automatic identification methods were researched based on time-series of MODIS—NDVI datasets. The characteristics of NDVI time series of winter wheat in China were firstly analyzed, and then the threshold values of extracting crop planting area were set and the extraction models of winter wheat were established, finally spatial distribution of winter wheat of 2010—2011 was obtained, the results showed that the extraction accuracy of winter wheat planting area was more than 81% compared with the average statistical data obtained in years. MODIS data of China in 2011 were used to monitor the growth condition of winter wheat, and the growth condition was compared with the average crop growth of the last five years. Results show that winter wheat growth condition has different characteristics both in spatial and temporal.