In China， inadequate historical wind data hinders the profiling of wind power fluctuation at the regional level， which is the fundamental work for the wind power integration. This paper proposes a method to assess the seasonal and diurnal wind power patters based on the wind speed data from the National Aeronautics and Space Administration（NASA） Goddard Earth Observing System Model， Version 5 Data Assimilation System（GEOS-5 DAS）. The Gipe formula is applied to get the vertical distribution of the wind speed. The wind speed is transformed into the electric power according to the power curve of Vestas V90-2.0MW turbine. A quantitative analysis is made for six wind power bases in China to present the difference of seasonal wind power patters and the regional correlations of hourly wind power patters. The method and results provide the basis for the regional wind power scheduling and dispatching.