Studying on soil moisture is the base of demonstrating ecosystem function and evaluating comprehensive environmental benefits of forest. The shelter belts of horizon and up and down of hill were selected in second and eighth small catchment of Hebei watershed in Heilongjiang to investigate the potential effects of shelter belt on dy- namic of soil moisture, soil water profile and soil moisture of cropland of two sides of shelter belt. The results showed that the shelter belt had no significant effects on dynamic and profile of soil moisture, but the depth of maximum soil moisture appeared were different. Influenced by runoff interception and shady produced by shelter belt, there were significant difference on soil moisture between up and down slopes, and between right and left sides of shelter belt. The soil moisture of inside and close to shelter belt was less than cropland.