Abstract: In order to research dry intrusion and Short-time Heavy Rainfall correlation in Inner Mongolia, understand the evolution and development of the actual system, and analyze and diagnose its impact on the short-time strong rainfall occurrence and development, the NCEP 1°×1° reanalysis data，FY-2C2D satellite images, conventional meteorological data and the method of combining satellite cloud images with atmospheric dynamic field were used to analyze the dry intrusion characteristics under the influence of cold eddy and the role of the dry intrusion during the short-time strong rainfall which occurred in Xingan league of Inner Mongolia on July 7, 2012. The results were as follows: (1) for this process, northeast cold vortex was the direct influence system, which had an obviously dry invade from the upper troposphere to the lower troposphere and the cold air of high vortex formed low humidity of upper troposphere to middle and lower troposphere, resulted in a vertical structure of lower layer with "upper dry and cold, under warm and wet" and was conducive to the formation of convective unstable stratification. In this case, the ground frontal baroclinity was very strong, so the lifting of warm and moist air promoted the formation of short-term heavy rain, and the rainy time was identical to the time of the strongest lower instability and in the area of upper and lowerθ_se dense distribution.(2) Comma cloud was formed in the infrared cloud image, the high value zone of brightness temperature of blackbody was corresponded with dry and cold zone, and brightness temperature gradient of convective cloud edge increased with the inserting of dry and cold area, and the center brightness temperature reached -53℃, short-time strong precipitation occurred in the east of the largest zone of brightness temperature gradient of convective cloud and the falling region of short-time strong precipitation was consistent to the moving direction of gradient larger area.