Using the surface observation, MICAPS and NCEP data from 1951 to 2013, the 700 hPa influence systems of 150 heavy snowstorms occurred in the southeastern Inner Mongolia are divided into seven types, and for the 26 heavy snowstorms from 2007 to 2013, the physical quantity fields are classified and analyzed for 25 stations. The results show: Overall, the divergence field had the characteristics of the lowlevel convergence and highlevel divergence, which corresponded to the coupling effect of high and low jet streams. The vertical velocity field and a long time strong updraft in the whole layer maintained. Depending on the height of the weather patterns, the maximum relative humidity was between 925 and 500 hPa, and the water vapor flux divergence/convergence was mainly between 925 and 700 hPa. With high elevation, the specific humidity rapidly decreased. The minimum humidity for various weather patterns at 925 hPa was 2 to 29 g〖DK〗·kg-1, and that at 850 hPa was 17 to 32 g〖DK〗·kg-1, reflecting the effect of the lowlevel southwest warm water jet, especially the contribution of the 925 hPa superlow jet stream. At the 1000 hPa (the 75th percentile) near the ground layer there was basically cold advection. Above 925 hPa there was all warm advection, which had obvious “cold cushion” effect and provided the trigger conditions for the heavy snowstorm.