Abstract: In order to investigate the detection differences between Taishan C-band radar (CDD) and Jinan S-band radar (SAD) on the strong precipitation squall line,two strong precipitation squall line processes in Shandong Province on October 2,2022 and June 27,2023 are selected,and the characteristics of echo intensity,differential reflectivity (Z_DR) and probability density of the overlapping observation area are compared and analyzed with the conventional meteorological data and radar data.The results show that there are significant differences in the detection of squall line echo intensity and Z_DR between the two radars,and the stronger the squall line,the greater the difference in detection between the two radars.low values of reflectivity factor detected by the CDD are significantly more and high values are significantly less.Stronger squall lines may have more negative Z_DR values.The Z_DR of the CDD at 3 km altitude has more high values of more than 4 dB,which is mainly caused by the liquid particles with larger sizes.The echo strength and Z_DR differences of both radars decrease with increasing altitude,and the detection values of the CDD at higher altitudes have higher confidence in capturing the cloud micro-physical features of the squall line better.The higher altitude of the CDD is conducive to the detection of high-level clouds,and the comparison with the SAD reveals that although there are problems such as weak echo strength,attenuation after strong echoes,and high false degree of double polarization features,it can also be able to show the feature differences in the stage of strong precipitation,and thus the two radars can effectively improve the observation capability of the SAD in the high-level blind zone.