Abstract: The paper is about field experiment of water-heat-salt movement of freezing-thawing soils in Yucheng Experimental Station,Shandong Province. The results of bare soil surface and plastic film mulched soil surface are compared and discussed. Mulching can increase the soil temperature, remain high water content and decrease the salt content in subsurface soil. So mulching through winter to next spring is a reasonable method to prevent the soil from suffering cold and arid, and decrease the salinity of the soils.