To investigate the effect of stand age on soil ecological stoichiometry and soil physicochemical properties in teak (Tectona grandis) plantations, an age sequence of Tectona grandis stands (10 years old, 32 years old, and 37 years old) were selected in the Qingshan Experimental Field of Tropical Forestry Experiment Centre of Chinese Academy of Forestry, Sino-Vietnamese border area, Pingxiang, Guangxi. Three representative 20 m×20 m plots were set in each representative part of each forest stand. Based on the principle of multi-point mixing, random distribution and the same quantity, soil samples were collected from 0-10, 10-20, 20-30, 30-50, and 50-100 cm depths, soil moisture-physical properties, pH, soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK) content were analyzed, C:N, C:P, N:P and C:N:P ratios were estimated. We explored their changes with forest age and the relationship between the above factors and the C:N:P stoichiometric ratio, in order to provide a scientific basis for sustainable management of teak plantation. The results showed that in addition to soil bulk density (SBD), available phosphorus (AP), available potassium (FK), C:P and N:P ratio, the forest age had significant effects on other soil physical and chemical properties and C:N ratio. The C:N and C:P increased with the increasing of forest age, the pure forest management of teak reduced C, N, and P reserves, and its growth was limited by P, appropriate mixing transformation was very important. The average values of the C:N ratio (7.32), C:P ratio (26.92) and N:P ratio (3.56) of the three forestry teak plantations in Daqingshan area of Guangxi were significantly lower than the average levels of the soil C:N ratio (11.90), C:P ratio (105), and N:P ratio (5.20) in the national, which indicated that the soil C, N and P were still very limited in the area. Pearson correlation analysis between soil SOC, TN, TP content, C:N ratio, C:P ratio, and N:P ratio showed that the correlation between C:N ratio and SOC was greater than the correlation between C:N ratio and TN, the correlation between C:P ratio and SOC was greater than the correlation between C:P ratio and TP, indicating that the soils C:N ratio and C:P ratio of teak plantation were mainly affected by the organic carbon content. It is very important to scientifically control the organic carbon content in the soil during the management of teak plantation. The lower C:N ratio and C:P ratio in this study area indicate that the organic matter decomposes quickly, which may be detrimental to the maintenance of teak plantation soil fertility due to abundant rainfall in the south subtropical.