Heat Exchanger and Refrigerant Module of Integrated Thermal Management System for Vehicle Including Same

An embodiment heat exchanger includes a first flow path through which a refrigerant discharged from a condenser and drawn into an expansion valve flows and a second flow path through which the refrigerant discharged from a vapor-liquid separator and drawn into a compressor flows, wherein the heat exchanger is configured to perform a heat exchange between the refrigerant flowing through the first flow path and the refrigerant flowing through the second flow path.