Complex process industrial parks serve as the core carrier of high-end manufacturing industries. This paper analyzes the coordination difficulties in the core process design, special supporting process design, civil engineering main structure design and secondary electromechanical design of complex process industrial parks, clarifies the responsibilities and collaborative relationship between the EPC general contractor and the construction unit as the two main parties in design management under the EPC model, and constructs a design process featuring "process priority, step-by-step information submission, and dynamic iteration". Taking the JIANHUA Leapmotor New Energy Vehicle Intelligent Lamp Industrial Park as a case study, this process is implemented in practice. The results show that the design cycle is shortened by 25%, effectively reducing design changes and rework, which provides a reference for design management under the EPC model for similar high-end manufacturing industrial parks.