Abstract: In the paper, we analyzed the environmental condition of the hailstorm in Beijing region on 23 June 2008 and the evolution characteristics of weather radar products by using the C band dual-polarization weather radar and NECP data. By detailed analysis of the polarization parameters ( ZDR、ρHV、KDP), some characteristics of hail clouds were summarized as follows. Strong echo occurred in the radar reflectivity map at high altitude, ZDR tended to be zero, and ρHV and KDP suddenly decreased compared to values at the surrounding areas. In addition, the role of KDP and ρHV played in distinguishing false echoes and judging echo development was analyzed. The above study is valuable in improving the application of the dual-polarization weather radar in strong convective severe weather monitoring and forecast, hail disaster mitigation,aviation security, etc.