This invention discloses a medical diagnosis system a control panel thereof. According to this invention, a USB technology is utilized to perform input via the human-computer interface of the medical diagnosis system. Except for completely compatible with the standard alphanumeric keys portion, the control panel further comprises specific function modules for the medical diagnosis system and the trackball module. The connection of all function modules of the control panel are implemented by one physical interface. Universal alphanumeric keys and the trackball, as well as the specific function modules for the medical diagnostic equipment, are integrated into a whole body, and communicate with the upper computer (PC) via one physical interface, thereby complexity in connecting the peripheral devices of the human-computer interface is reduced, Plug-and-Play can be supported, and the use of it is easier and more convenient.