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The objective of this paper is to discuss the effects of mulching methods on freezing and thawing characteristics of salinized soil and the autumn irrigation quality in cold—drought—salt irrigation district. The field freezing and thawing experiments were conducted with the mulched salinized soil in Hetao Irrigation District. The experiments included five treatments: chopped maize straw 0.9kg/m2 (F0.9), chopped maize straw 0.6kg/m2 (F0.6), whole maize straw (YZ), plastic film (DM) and no mulching (CK). The results showed that the heat transport capability of different soil layers was affected by surface mulching after autumn irrigation. Mulching affected the process of soil freezing and thawing and changed the response correlation of the soil frozen depth to the negative accumulated temperature. The soil frozen depth variability during the freezing period can be assessed and predicted by the available negative cumulative air temperature. Results revealed that all mulching treatments improved the soil water storage in the maize sowing time for following year at depth of 0~10, 0~40 and 0~120cm significantly compared with CK. The soil salinity in the surface layer (0~10cm) and plough layer (0~40cm) was drastically lower than that of CK. The salt control effect of whole maize straw YZ was superior to the other treatments. The suitable sowing date of spring maize under plastic film mulching was advanced by 7d relative to CK, while the straw mulched date was delayed by 6~7d. Mulching measures improved the maize seedling emergence rate significantly，the emergence rate of maize of YZ and F0.9 were considerably higher than F0.6 and DM. The results could be used to guide the research of autumn irrigation scheduling under mulching situations in Hetao Irrigation District.