The effects of water-source conservation of soil and water conservation forests paid a good deal attention to recently. In this paper, the researches was conducted in the stands of Pinus ellfottfi, mixed stands of Alnus crenastogyne and Cupressus ~unebris, the shrub of Robfnfa pseudoacacfa, the stands of Robinnia pseudoacacia and the stands of Alnus crenastogyne, which had been established and naturally restored in late 1980s. The mechanism and the effects of water conservation were deeply studied based on the indexes of factors as following: interception of canopy , soil bulk density, soil porosity , water-holding capacity, penetrability of soil and water holding characteristics of litter. The results show that the effect of every conservation forest was significantly superior to farm land. Among the models of protective forests studied, the effects are significantly different. Some more effective models of vegetation arrangement were suggested as following: The mixed forests of Alnus crenastogyne and Cupressus~funebris, the stands of Pinus ellyottii, Alnus renastogyne etc.