Abstract:About 60% of the problems in the project are caused by poor interface management. In the Chinese context, to bring forward a better way to solve the interface management problem, this study used the theory of planned behavior, took the low-trust construction market environment as the background and the subjective psychological factors of organizational interface management behavior as the perspective, and used structural equation model to construct a multi-factor mediation model. Then this study verified the relationship between trust and organization interface management behavior and its psychological impact mechanism based on the survey data of 295 personnel in Engineering-Procurement-Construction(EPC) projects. The results show that the influence of trust on the organization interface management behavior intention is mainly transmitted through three mediating variables: attitude, subjective norm, and perceived behavior control. Among the three mediation paths, the mediation effect of attitude is the strongest, while the mediation effect of perceived behavior control is the weakest. It indicates that internal psychological factors are an essential prerequisite for the formation for the formation of organization interface management behavior intention. However, the positive attitude of EPC projects managers towards organization interface management behavior in China is not fully translated into perceived behavior control, and that some managers have given up implementing organization interface management due to their weak ability to control resources. Therefore, the countermeasures for the organization interface management of EPC projects in Chinese context were proposed from the two aspects of the owner and the general contractor respectively.