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Soil mulch is one of the important agricultural measures, in order to inquiry the mechanism and characteristics of the mulching hindrance effect on heat exchange between atmosphere and soil. There were four treatments of bare land, natural snowfall mulching, 5cm straw with natural snow fall mulching and 10cm straw with natural snow mulching in winter field trial period (2016.11.1—2017.4.30), the total soil water content, liquid water content and temperature at the soil depths of 10cm, 20cm, 30cm, 40cm, 50cm, 60cm, 70cm, 80cm, 90cm and 100cm under the four treatments were determined, the heat capacity, phase change heat and heat quantity of freezing-thawing soil were calculated, and then the effects of different mulching treatments on heat spatial distribution and transfer efficiency in freezing-thawing soil were analyzed. The result showed that the depth of 30cm soil heat exchange was accounted for relatively large, the heat quantity was accounted for up to 54.57%~81.17% in different trial periods. In the freezing period, the soil heat transfers of four treatments showed the heat dissipation overall trend, and in the thawing period, the soil heat transfers of four treatments showed the heat absorption overall trend. The effects of the natural snowfall mulching, straw mulching of 5cm and 10cm on the heat transfer rate were 17%, 8% and 17%, respectively. The time periods of no soil heat change were long with proportions of 29.17%, 39.41%, 43.33% and 50.88%, respectively under different treatments. The study had practical significance for the spring soil moisture conservation.