Heat Pump System of Vehicle

An embodiment heat pump system of a vehicle includes a first cooling device including an electrical component and a first line for circulating a coolant, a second cooling device including a battery module and a second line for circulating the coolant, a HVAC module connected through a refrigerant line and internally provided with an opening/closing door that adjusts a selective flow of ambient air according to a cooling, heating, or heating and dehumidifying mode of a vehicle interior, a heat-exchanger connected to the internal condenser through the refrigerant line, a first expansion valve on the refrigerant line and connecting the heat-exchanger and the evaporator, a compressor connected between the evaporator and the internal condenser through the refrigerant line, an accumulator on the refrigerant line between the evaporator and the compressor, a chiller, a second expansion valve, a third expansion valve, and a second connection line.