Abstract: Based on the analysis of three kinds of wind retrieval techniques with Doppler radar, Velocity Azimuth Processing (VAP) technique is considered to be used in operation in the near future, and the key of which is whether the wind field information on meso-β scale and larger scale is filtered out from initial data, in order to eliminate the influences of the wind field information smaller than meso-V scale on retrieval results. Therefore, the pre-processing of data is made using 2-D low pass filter method. In addition, the wind velocity computational formula of VAP method is improved.