Aiming at the problems of insufficient operational flexibility and low economic benefits caused by the shortage of adjustment resources of the park-level integrated energy system (PIES), this paper coordinates and considers two measures of residential users participation in integrated demand response (IDR) and the addition of energy storage and conversion equipment, and proposes an economic optimization method for PIES. First of all, a IDR model including price-type and incentive-type loads on the basis of considering the adjustment capabilities of equipment such as air-conditioning and gas heating is established. Secondly, the behavioral characteristics of residential users participating in demand response is analyzed. Then a correlation model between room temperature deviation and user participation. Finally, an economic optimization model of PIES is constructed that takes into account the IDR and equipment expansion. The analysis of an example shows that the proposed economic optimization method fully considers the participation of residential users in comprehensive demand response, adjusts resources and optimizes the allocation of additional equipment capacity, which effectively improves the economy of PIES.