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In order to better understand the macro and micro structure characteristics of snow clouds, the vertical structure and evolution of a frontal snowfall process on February 14, 2019, are examined using the dataset of Micro Rain Radar (MRR) and Ka-band Cloud Radar (CR) combined with aircraft observation at Huangsi national meteorological station in the south-central part of Hebei Province. The results are as follows: During the initial stage of snowfall, there was a double-layer cloud structure with a dry layer in the middle. The cloud top and base height of the medium cloud were about 4100 m and 3600 m, respectively. The height of the low cloud top and bottom were 3100 m and 200 m, respectively. The growth of particles below 3000 m in the lower cloud was mainly due to the process of rime attachment. During the snowfall development stage, the upper and lower layers of cloud were connected, and the amount of snowfall on the ground was larger in the period with stronger radar echo intensity. The snowfall process in this period was mainly dominated by condensation and aggregation growth. During the late stage of snowfall, the maximum echo intensity and the cloud top height decreased. The echo intensity, doppler velocity and spectral width increased with the decreasing height below 3000 m. Aircraft observation results show that due to the thin water cloud, it was unsuitable for catalytic operation at the bottom of the inversion layer during the late snowfall period. Ice and snow particles were mainly located in the middle and upper part of the cloud and grew bigger during the falling process as the height decreased, which is consistent with radar observation. The correlation coefficient between millimetre wave cloud radar/MRR reflectance and the effective diameter of precipitation particles were 0.89 and 0.83, respectively. Radar reflectivity factors were mainly dominated by largescale particles such as ice and snow crystal particles.