The depth of three types of soil layers (0-40 cm, 0-80 cm, and 0-120 cm) in Daguan County, Yunna Province were chosen as the research object to analyze the biomass allocation characteristics of Q. tumidinoda components at the individual level and their relationship with soil physical properties. This study provided a theoretical guidance for the selection of suitable site conditions, the suitable sites of bamboo and directional cultivation. The results showed that: (1) at the same soil depth, soil water content, maximum water holding capacity, capillary water holding capacity, capillary porosity and total porosity increased with the increasing of soil layer, while soil bulk density and non-capillary porosity decreased with the increasing of soil layer. There were significant differences in soil physical factors between thin and thick soil layers (P<0.05). (2) With the increasing of soil layer thickness, the total biomass and biomass of culm, branch, leaf, stump, rhizome and root of Q. tumidinoda presented increasing trends, and there was significant difference among the thickness of different soil layers (P＜0.05). (3) With the increasing of soil thickness, the biomass allocation of branch, leave, stump, rhizome and root increased, while the biomass allocation of culms decreased, but there was no significant difference among the treatments (P＞0.05). (4) Soil physical factors had significant effects on biomass allocation of Q. tumidinoda components (P＜0.05). The order of importance of single soil physical factor to biomass allocation characteristics of Q. tumidinoda components was soil water content＞total porosity＞maximum water holding capacity＞bulk density＞capillary porosity＞capillary water holding capacity＞non capillary porosity. In conclusion, the changes of soil physical factors along the soil thickness had an important influence on the biomass distribution of Q. tumidinoda components. In the environment with poor soil physical properties, Q. tumidinoda would preferentially allocate the biomass to the culm and reduce the leaf biomass to respond to the adverse environment of water loss. This was of guiding significance to the selection of site conditions of Q. tumidinoda forest, that was, Phyllostachys pubescens should choose deeper soil layer for management, so as to promote biomass accumulation and population growth.