[Objective] The influence of soil moisture content and dry bulk density on the shear strength of soil in the study area was explored and an empirical formula was established in order to provide a theoretical basis for improving the stability of the slope and protecting the soil and water environment.[Methods] Three typical forest stands (evergreen broadleaved forest, coniferous and broad-leaved mixed forest, shrub-grass forest)was sampled in Fengyang Mountain Nature Reserve, Zhejiang Province. Remolded soil direct shear experiment was conducted to analyze the effect of different classification of moisture content (25%, 27%, 29%, 31%, 33%) and dry bulk density (0.8, 0.9, 1.0, 1.1, 1.2 g/cm) on the shear strength parameters (the internal frictional angle φ and cohesive force c).[Results] ① There were a significant positive correlation between cohesive force and dry bulk density, and a significant negative correlation between cohesive force and moisture content. There was a significant positive correlation between the internal frictional angle and the dry bulk density. ② The soil cohesive force decreased with the increase of moisture content, and increased with the increase of dry bulk density, it had obvious regularity; with the increase of dry bulk density, the internal frictional angle had a tendency of obvious increase, which in the case of high compactness, the internal frictional angle was always large. In relate to the cohesive force, the internal frictional angle was less affected by the moisture content. With the increase of the moisture content, the characteristics of non-linear decrease in shrub-grassland forests and coniferous and broad-leaved mixed forest were showed. In the evergreen broad-leaved forest, there was a trend of increasing first and then decreasing, considering the occurrence of optimal moisture content. ③ At the same moisture content, the dry bulk density had an enhanced effect on the cohesive force of the three types of soils. The logarithm of cohesion and the dry density showed a positive linear correlation. We consider the combined effects of moisture content and dry bulk density, add the influence coefficient β, and establish an empirical formula, respectively.[Conclusion] The logarithm of cohesive force and moisture content were significantly negatively correlated with each other, and there was a significant positive correlation with dry bulk density and cohesive force. Soil dry bulk density had a significant effect on soil internal frictional angle, and moisture content had no significant effect on internal frictional angle.