In order to compare the difference of mesocyclone identifications between S-band dual polarization radar (SPOL) data and X-band phased array weather radar (XPAR) data, based on the SPOL and XPAR and ground observation data, a small and medium scale weather process that occurred in Guangzhou on 19 April 2019 is compared and analyzed. The results show that the identification algorithm used can correctly identify the mesocyclone. The high spatial-temporal resolution data of XPAR can make up for the lack of SPOL elevation layer, and more complete vertical structures of mesocyclones were observed. The parameters in the identification results were more detailed than those in SPOL, which revealed the short-term evolution of mesocyclone more accurately. In conclusion, compared with SPOL, XPAR has the advantages of longer duration, more fine vertical structure, larger difference between positive and negative velocity extremum, and more detailed evolution with the whole weather process. This is conducive to the detailed and in-depth study on the rapid development and evolution of mesoscale weather system.