In order to study the market mechanism and clearing strategy of virtual power plants participation in integrated demand response, an integrated demand response market mechanism and clearing strategy considering the adjustable capacity of virtual power plant are proposed. Firstly, the mechanism of virtual power plant participating in the integrated demand response market is analyzed, and the integrated demand response resource model considering the internal resources of virtual power plant is established. Then, the mathematical model of adjustable capacity of virtual power plant is proposed and solved by improved particle swarm algorithm. Finally, the integrated demand response market clearing strategy considering the adjustable capacity of the virtual power plant is proposed, and the interactive clearing method of the superior distribution network and the virtual power plant operator optimization strategy is designed. The results show that the integrated demand response market clearing strategy in this paper can reduce the total cost on the basis of ensuring the interests of virtual power plant operators, and achieve peak load shifting and new energy consumption.