At present, the next generation weather radar in China is upgrading to the dual polarization system. The accurate measurement of differential reflectivity (〖WTBX〗Z〖WTBZ〗DR) of meteorological targets by the CINRAD/SAD dual polarization weather radar is an important part of parameter calibration. For Xuzhou dual polarization radar, 〖WTBX〗Z〖WTBZ〗DR calibration test for Xuzhou radar was carried out with UAV (Unmanned Aerial Vehicle) carrying two kinds of standard metal spheres, respectively. In this test, the VCPsect scanning mode was configured, the fan scanning combination of target azimuth ±5° was adopted and all radar filtering algorithms such as ground objects were turned off. The results show that the average value of 〖WTBX〗Z〖WTBZ〗DR was 0.265 dB, the minimum was -0.125 dB and the maximum was -0.375 dB, when the 40 cm metal sphere was used, and the distance between UAV and metal sphere was 68 m. The values of ZDR meet the technical requirements of radar 〖WTBX〗Z〖WTBZ〗DR calibration. The research provides a technical solution for operational radar to carry out dual polarization radar 〖WTBX〗Z〖WTBZ〗DR calibration.