Abstract: The present invention provides a packaging method and a packaging structure for a cascode power electronic device, in which a hetero-multiple chip scale package is used to replace the traditional die bonding and wire bonding packaging method. The cascode power electronic device can reduce the inductance resistance and thermal resistance of the connecting wires and reduce the size of the package; and increase the switching frequency of power density. The chip scale package of the present invention uses more than one gallium nitride semiconductor die, more than one diode, and more than one metal oxide semiconductor transistor. The package structure can use TO-220, quad flat package or other shapes and sizes; the encapsulation process of the traditional epoxy molding compounds can be used in low-power applications; and the encapsulation process of ceramic material can be used in high-power applications.