Provided are an electronic device and a method of manufacturing the same. The device includes a plastic substrate, a transparent thermal conductive layer stacked on the plastic substrate, a polysilicon layer stacked on the thermal conductive layer; and a functional device disposed on the polysilicon layer. The functional device is any one of a transistor, a light emitting device, and a memory device. The functional device may be a thin film transistor including a gate stack stacked on the polysilicon layer.