Integrated energy planning technology is widely used in power system planning and design. Based on a variety of energy requirements, a multilayer integrated energy planning method is discussed in this article, which includes a four-layer energy supply method, smart grid planning, and control system model application. Following the integration and application technology of the planning methods analysis, the application of integrated energy planning in the energy system for Mingzhu Industrial Park is introduced as a case study, with the conclusion that this verifies that an integrated energy planning method could effectively reduce the cost of distribution planning and improve load characteristics.