Abstract: In order to better recognize the formation mechanism of rainstorm in Shanxi Province, based on infrared radiation bright temperature, Doppler radar data and total air column water vapor content data, the multi-scale characteristics of a strong convectional rainstorm occurred in Shanxi on July 3-4 of 2013 were analyzed. The results showed that: (1) while the warm shear lines on 700 hPa and 850 hPa were meso-α scale triggering systems, the shear lines of extreme wind of automatic stations and cyclonic vortex were the meso-β scale systems which jointly acted to trigger the strong convectional rainstorm. And the meso-γ scale cyclone directly led to the heavy storm. (2) Between the shear lines on 700 hPa and 850 hPa, the cloud clusters emerged and developed near shear lines of extreme wind of automatic stations and cyclonic vortex, which directly resulted in multiple rainfall peaks of rainstorm center. (3) The vertical structure of the cloud brought Yangcheng Liaohe the first rainfall peak was the cold cloud top at a lower temperature threshold (-53℃) which was ahead of the area where the radar reflectivity was more than 40 dBz, while the cloud that caused the second rainfall peak in Yangcheng Liaohe had a vertical structure that the geometric center of the cold cloud top overlapped the region where the radar reflectivity was greater than or equal to 45 dBz.