Because of its small size, low cost, perfect function, and stable performance, X-band weather radar provides fine observation data as a supplement for the new generation of weather radar in the low-level blind area, mountainous area, and key monitoring area. In recent years, Yunnan Province builds a number of X-band dual-polarisation weather radars to supplement the detection blind spots of the new generation of weather radar observation network and improve the coverage of radar observation in the province. In order to effectively improve the accuracy of multi-system radar network observation, the heavy rainfall weather process occurring in Kunming and Dehong Prefecture and their surrounding areas on 28 July 2023, is selected, and the data of synchronous observation bodies in Kunming, Chenggong, Dehong, and Yingjiang are taken as an example to compare the radar echo intensity of different time and elevation combinations. The consistency of echo intensity between adjacent C-band weather radar and X-band weather radar in Yunnan is analysed. The results show that both X-band weather radar and C-band weather radar can accurately reflect the intensity change of precipitation, but there is a certain deviation in the measured echo intensity; the former is larger than the latter. In the same observation area, the echo shapes of the two radars at different times and elevation angles are basically the same, and the echo generation, extinction, and change trend are consistent, correctly reflecting the intensity change of precipitation. The strong centre of the echo appears in the same position, but the strong centre of the X-band weather radar is more prominent. At the same time, the echo intensity of X-band weather radar is generally higher than that of C-band weather radar. The average echo value of Chenggong radar is 3.5 dBz higher than that of Kunming radar, and the maximum echo value is 15.5 dBz higher, and the average echo value of Yingjiang radar is about 5 dBz higher than that of Dehong radar, and the maximum echo value is 19.5 dBz higher. In the same observation area, C-band weather radar has more weak echoes, X-band weather radar has more strong echoes, and the peak echo intensity of X-band weather radar is greater than that of C-band weather radar. Comprehensive analysis shows that radar hardware difference, calibration inconsistency, beam blocking, altitude inconsistency, atmospheric attenuation, atmospheric environment difference, and so on are the factors that cause the echo intensity inconsistency between adjacent radars. Therefore, it is necessary to carry out unified system calibration and radar echo intensity attenuation correction to improve the accuracy and consistency of radar network observation.