Pinus yunnanensis is the main dominant species and plays an important role in southwest China. An empirical model was provided to study growth dynamics of P. yunnanensis with global climate warming using a stand growth model and analyzing the relationship between parameters of an optimal model and a model with environmental impact factors. The growth model for average DBH of a stand was established with a nonlinear regression model. The model was based on data in the continuous forest inventories (CFI) for Yunnan Province along with meteorological data and then combined with six kinds of fundamental theoretical equations. Results showed: (1) the Gompertz Model was selected from the optimal model using the parameters of maximum coefficient of determination (R2 = 0.648) and the minimum root mean square error (RMSE = 3.384). (2) The degree of influence for environmental impact factors on the DBH growth model was humidity index>altitude>mean annual precipitation>potential evapotranspiration>mean annual temperature>warmth index>canopy density> soil thickness>slope. (3) The relationship of average DBH growth of the stand to topographic factors and climatic factors were positive or negative. Topographic factors, such as slope, had little effect on stand DBH growth. Also, temperature influenced mean DBH growth through control of precipitation. In conclusion, the best model introduced environmental factors as a combination of the two parameters (R2 and RMSE) to explain the influence of environmental factors on average DBH of the growth model.