Based on the field observation data in the source region of the Yellow River from October 2011 to December 2017, the characteristics of soil freezing-thawing duration, soil temperature and moisture, surface energy components in high snowfall year and low snowfall year were analyzed in this paper. The results show that the snowy year has higher albedo, lower net radiation, and lower surface heat transfer than the less snowfall year. The time of the snowy year from the heat "source" to the heat "sink" is later than the less snowfall year. Snow accumulation can reduce the radiant energy absorbed by the soil, reduce the sensible heat transfer on the surface, increase the surface latent heat transport during the frozen period and the thawing period of the soil, reduce the heat transfer from the soil to the atmosphere during the frozen period, and reduce the heat transfer from the atmosphere to the soil during the thawing period. The snow cover has a cooling effect in the freezing period, which makes the soil freeze earlier in the snowy years and the soil temperature is lower in the same period. It has the function of heat preservation in the frozen period, which makes the soil temperature higher in the snowy years. In the thawing period, it has the effect of heat preservation ("cooling"), which makes the ablation later and the soil temperature is low in the same period. During the whole freezing-thawing period, the shallow soil moisture in the snowy year is higher than that in the less snowy year, indicating that the snow has a moisturizing effect on the shallow soil. Snow accumulation makes the soil to start freeze earlier and the start of ablation later, which can extend the number of days that the soil is completely frozen.
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