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The objective was to clarify the effects of the snowmelt on cropland soil moisture in spring of the high latitude cold region in China. The Hulan River Basin, which locates at the middle Heilongjiang Province, was adopted as the study area. In consideration of the deficiencies of spatial and temporal resolution of monitoring station data, remote sensing data and land surface model assimilation data, the hydrological processes such as snowfall, snow cover, and snow melting were simulated using soil and water assessment tool (SWAT). Research on spatial and temporal characteristics of snowfall, snow cover and snowmelt and their effects on the cropland soil moisture in spring of the Hulan River Basin were carried out. The results indicated that the spatial distributions of the average snowfall, the maximum daily snow cover, snowmelt within the Hulan River Basin showed a similar characteristic that gradually increased from west to east;the change rates of snow cover, snowfall and snowmelt exhibited the similar spatial distribution characteristics and these change rates showed increasing trend at most areas within the basin;the close relationships existed among the series of annual snowfall, snow cover and snowmelt, that were similar to the interannual variation trend of soil moisture, and the interannual variation of cropland soil moisture was greatly affected by precipitation. A related significant correlation existed between the snow cover in a period from the last November to the current March, the snowfall in the last November, snowmelt in current April, and the cropland soil moisture in April and May of the current year. The snowmelt water recharged the soil moisture from the late March to the early April, which could promote the shortterm increase of soil moisture, and the amount of snow cover determined the replenishment of snowmelt water to cropland soil moisture;the change trends of soil moisture were gently decreased before snowmelt, whereas significantly decreased after snowmelt ended.