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Droughts are the main agrometeorological disasters during winter wheat growth periods, which seriously influence the growth and yields of winter wheat. Taking the winter wheat growing area of Anhui Province as an example, based on the daily meteorological data from 36 meteorological stations of the winter wheat area from 1960 to 2012, the Crop Water Deficit Index (CWDI), Comprehensive meteorological drought Index (CI), Standardized Precipitation Index (SPI) and Precipitation Anomaly percentage (PA) are calculated, and the four kinds of drought indices are compared and analyzed. The results show that PA and SPI are extremely consistent in crop growth season. The temporalspatial distributions of drought days calculated by the four drought indices are consistent in winter wheat growth season in total. SPI and PA indices have excellent stability of computation. However, they do not consider the expenditure of water, so that they are easy to exaggerate the level of drought； CI and CWDI indices take both recent rainfall situation and water balance into account, and can better characterize droughts. Considering the crop coefficient, CWDI can reveal the status of crop water deficiency and drought events in winter wheat growing season especially. In addition, according to correlation analysis between yield reduction rate and four drought indices, CWDI has better applicability in the monitoring and evaluation of drought development of winter wheat in Anhui.