The invention relates to the field of electrostatic drying, in particular to a heat pump electrostatic combined drying system and a working method thereof. The heat pump electrostatic combined dryingsystem comprises a heat pump system, a static electricity generation system and a circulating air system. The heat pump system comprises an air-cooled condenser, an air-cooled evaporator and a micro-compressor. The static electricity generation system comprises a static electricity generator and an electrostatic plate. The circulating air system internally comprises an electric heater, a drying oven, a fan I and a fan II as well as an air-cooled condenser and an air-cooled evaporator. According to the heat pump electrostatic combined drying system and the working method thereof, an electric heater system in a traditional drying machine is replaced with a heat pump; compared with a traditional electric heater, the heat pump system is better in energy saving effect; an electrostatic drying device is additionally arranged, the diffusing speed, towards the surface, of water molecules can be increased through electrostatic drying, evaporation of water on the surface of food is accelerated,thus the drying process is accelerated, and the material drying quality is good.