In this study, five typical forest lands (Poplar Populus×Quercus liaotungensis natural secondary forest, Pinus tabulaeformis×Robinia pseudoacacia mixed forest, artificial Pinus tabulaeformis forest, artificial Robinia pseudoacacia forest, and artificial Platycladus orientalis forest) in the Caijiachuan watershed of the loess area in west Shanxi were selected as the research object. A soil moisture observation point was placed in the center of each plot, and the soil volumetric water content from January 2016 to December 2018 were determined by the TRIME-TDR soil moisture analyzer, and the soil moisture in 0-200 cm soil layer was determined stratified with every 20 cm respectively in the early, middle and late of each month. Then the annual variation and the vertical variation of soil moisture in different forest types were analyzed. The results showed that (1) annual variation of soil moisture in different forest lands in this study area could be divided into four periods, including stationary period (January-March), fluctuation period (April-June), growth period (July-September) and consumption period (October-December), and the average soil water storage of the five forest types during the year followed the order of the natural secondary forest land (338.68 mm) > artificial P. tabulaeformis forest (319.74 mm) > artificial P. orientalis forest (314.15 mm) > the mixed forest land(303.37 mm) > the R. pseudoacacia forest (292.03 mm), and the water consumption of R. pseudoacacia forest land was the highest. (2) At the end of the rainy season, the soil moisture of the five forest types in the study area was positively supplemented, and the soil water recovery capacity followed the order of natural secondary forest land > coniferous forest land > mixed forest land > R. pseudoacacia forest land. (3) The vertical change of soil moisture in the study area could be divided into two layers, including the rapid change layer of soil moisture content and the relatively stable layer of soil moisture content. As the soil layer depth increasing, the average water content of different forest profiles generally increased first and then decreased. Surface soil moisture content of different forest types followed the order of P. orientalis forest > natural secondary forest land > P. tabulaeformis forest > mixed forest land > R. pseudoacacia plantations. Replenishment depth of soil moisture followed the order of natural secondary forest land > coniferous forest land > mixed forest land > R. pseudoacacia forest land.