Properties of humus and contents of aggregates in the soils on the Gaoligong Mountains were studied in the lab and through field survey as well to gain a better knowledge about characteristics of the soils in the Gaoligong Eco-system and provide a scientific basis for soil erosion controlResults show that composition of the soil humus therein demonstrated apparent zonality, and its contents of organic matter, humic acid, HA/FA increased first and then decreased with declining elevation. Humic acid and fulvic acid in A₁ layer followed a decreasing order of dark brown＞brown＞brown coniferous forest soil＞subalpine meadow soil＞yellow brown＞yellow＞yellow red soil in content, while those in A₂ layer did one of dark brown＞brown＞brown coniferous forest soil＞yellow brown＞yellow＞sub-alpine meadow soil＞yellow red soil. The HA and FA in A₂ horizon was higher than those in A₂ horizon in molecular complexity and chemical stabilitySoil aggregates, 1～0.5mm and＜0.25mm in particle size, occupied an overwhelming majority, accounting for about 60%~70% of the soil, and decreased in particle size with declining elevation, displaying a pattern of lognormal distribution. Negative correlations were observed of their geometric mean diameter with geometric standard deviation and soil erodibility K-factor, while a positive correlation was between geometric standard deviation and soil erodibility K-factor. Moreover, the soil also demonstrated some fractal features. Subalpine meadow soil was the highest among the soils in Dg and MWD but the lowest in δg, soil erodibility K-factor and CFD, and its soil structure stability and resistance to erosion was relatively stronger. The content of humic acid is believed to be an important factor, influencing soil stability.