A case structure of an electronic device is used for directly integrating an antenna of a signal transceiver circuit and a case of the electronic device, so as to improve a space utilization rate of the electronic device. At least one trench pattern is formed on a specific region of the metal case of the electronic device. When the metal case is electrically coupled to the signal transceiver circuit of the electronic device, the metal case and the trench pattern constitute at least one antenna of the electronic device.