In recent years, the increasing construction projects in China have played a positive role in promoting local infrastructure construction. In engineering construction, management mode is an important content, which must be understood. At present, EPC is a more commonly used project management mode, which has important significance and function in the current engineering construction. The general contractor is responsible for the design, construction, supply, installation and implementation of equipment and supplies until the project is qualified and delivered to the owner. EPC mode has clear main responsibility characteristics, which can stimulate the enthusiasm of the general contractor, make full use of the advantages of the combination of project management and preliminary design, and promote the coordination of cost saving. Shorten the construction period and improve the project quality. Although the EPC mode of China's construction projects started late, with the sustainable development of the company, more and more engineering projects adopt EPC mode for contract construction. EPC contract can effectively reduce the excessive management pressure of the contractor in charge of the contract owner, and greatly reduce the coordination between the design department and the construction department and other project participants. And can quickly manage the safety performance of construction design. There are differences in technology selection and project function. Through PSO algorithm and engineering technology configuration model, this paper makes a series of research and Discussion on construction site management under EPC contracting mode. In addition, it can effectively control the cost and schedule of construction projects. EPC contract management in the whole process of planning, procurement and construction can accurately determine the project cost and construction period, and provide security for the planning and use of project funds. The experimental results show that under the EPC contracting mode, the construction unit needs to have strict requirements on site management in order to make the project smoothly.