The present study was conducted with an innovative approach and the integration of system dynamics with ground theory to provide a system model for commercial soft technology diffusion in Iran's oil industry and was carried out in two stages. In the first stage, the ground theory was used. An interview with the 19 experts who dominated the process of commercial soft technology diffusion in the Iranian oil industry was carried out and a total of 785 final code, 184 concepts and 71 sub categories were extracted by performing necessary coding. The key variables of the system model were extracted from the first stage coding and a system model was developed in the form of 18 reinforcing loops and 4 equilibrium loops. In the following, the stock flow model was prepared, the necessary formulation was performed and after the validation of the model, the necessary simulations were done. The model data was gathered through expert comments and the model was simulated for a period of 50 years from 1390 to 1440. The results indicate that the best priority for improving the process of commercial soft technology diffusion is train, create an appropriate organizational structure, outsourcing and, ultimately, research and development.