In this paper, we surveyed regional snow process in Liaoning Province in the past 10 years, using the regular observation data and NCEP 1°×1°data. It can be divided into two types, one is north vapor transmission channel (we call it the north type), and the other is northeast vapor transmission channel (we call it the northeast type). We compared and analyzed two different types of snow that happened on November 16, 2002 and December 19, 2004, based on circulation, water vapor and dynamic conditions. The results show that the moisture conditions of the north type is better than the north-east type, but the dynamic conditions of the north type is weaker than the northeast type. We analyzed the physical threshold ranges of moisture and dynamic conditions. It shows that the specific humidity and flux at the 850 hPa of the north type is greater than the northeast type at the same level of snow. The water vapor magnitude at 850 hPa of the north type in heavy snow is as near as the snowstorm of the northeast type. The maximum of the helicity, the divergence at 850 hPa, the vertical velocity and the jet stream at 850 hPa of the northeast type is greater than the north type. The gap is more obvious when the level of snowfall is higher. The maximum of the vertical velocity and the jet stream at 850 hPa in the blizzard reached dynamic condition necessary for heavy rain.