The invention discloses a planning and design method of a regional integrated energy system. The planning and design method of the regional integrated energy system comprises the steps that an electrical load timing model in a region is built, a cold and heat load timing model is built, and an energy supplying technology model is built; a regional integrated energy system planning target is determined, and an overall planning target of the regional integrated energy system is set; index calculation and scheme evaluation are conducted; an optimal integrated energy system planning and design scheme is determined according to evaluation of all alternative options. According to the planning and design method of the regional integrated energy system, a complete idea and method of the planning and design of the regional integrated energy system are provided, the planning and design are guided through operation of the integrated energy system, the integrated energy system index in the complete period can be evaluated more accurately, and the optimal integrated energy system planning and design scheme can be determined. In addition, the model with the energy-saving technology and the electrical energy alternative technology is applied, an alternative collection of the integrated energy system design scheme is built, and rich alternatives are provided for the optimal design scheme.