The data from C band dual polarization weather radar and rainfall data from automatic weather stations during 12 synoptic processes in 2011 in Beijing are used for the value distribution calculation of ZDR, KDP and ρhv, with emphases on the effectiveness and errors of rainfall measuring by means of four radar rainfall estimation equations. The application of dual polarization weather radar products to hydrometeors identification is discussed by using some actual examples. It is concluded: (1) ZDR, KDP and ρhv can be enlarging gradually as rainfall intensity increasing; ZDR of hail is negative, and KDP of hail is larger than that of heavy rains, but smaller than that of torrential rains; ρhvof both light and moderate rainfall exceed 090, but the mean value of hails is only 0804 (2) The four radar rainfall estimation equations all overvalue the light and moderate rains and underestimate heavy rains, but the measuring errors of three rainfall estimation equations containing ZDR and KDP are smaller than that of the 〖WTBX〗I〖KG-*8〗〖CD*2〗〖KG-*8〗Z〖WTBZ〗H equation. As for short term rainstorms, the effectiveness of these three equations has obvious improvement, and the best is the I〖CD*2〗KDP〖CD*2〗〖KG-*8〗ZDR equation. (3) The case analysis of hydrometeors identification indicates that the estimate of hydrometeors (such as hail) is more direct and effective by using dual polarization products, which can reveal the hydrometeor phase state more clearly and judge the height of the 0 ℃ layer bright zone.