The invention relates to a peripheral device, an operating method of the peripheral device and an electronic device with the peripheral device. The peripheral device can be communicated with a system terminal and comprises a control unit and a touch display and operating body, wherein the control unit dynamically receives system state information from the system terminal; the system state information is at least relevant to either a current state and a current executing program of the system terminal; the touch display and operating body is controlled by the control unit; and the control unit selects one out of a plurality of preset keyboard layouts as the current keyboard layout according to the system state information, and allows the touch display and operating body to display the current keyboard layout for operating. According to the peripheral device, the operating method of the peripheral device and an electronic system applying the peripheral device, the keyboard layouts can be dynamically changed with different states or executing programs of the system terminal.