Abstract: The paper has studied the variation，seasonal dynamics，and affecting factors of soil moisture content in silting coastal area of Jiangsu Province．The results show that soil moisture content has obvious seasonal variation．which is influenced by stand．In spring，the water content of forest land is higher than that of farmland，which is more obvious with the forest age increasing．There is a great effect of tree roots on soil moisture content，the older the age is，the deeper the effect is．Soil moisture content in different seasons has significant difference，from the top soil to the bottom ，the difference decreases．Applying stepwise regression(the fiducial degree is 0．05)，the equation of soil moisture content(y)can be expresed：y=486.709+2.061X₄+1.786X₉-4.451X₁₀(R=0.830，X₄：content of waterstable granule，X₉：rain fall before 15d，X₁₀：evaporalion from water surface)．