Abstract: A system for switching an opened window in a computer system between a display state and a hide state includes a mouse and a window switch system. The mouse has a switch key and a signal control unit. The window control system includes a window recording unit, a display control module, a window state switch module and a signal processing unit. When the user presses the switch key to output a switch signal from the mouse to the window control system, the window state switch module changes the state of the opened window, and then, the display control module executes the altered result and outputs the result to the screen in the computer system, thereby achieving the purpose of switching the computer window between the display and the hide states, so as to prevent the information shown on the screen from being seen by unauthorized persons.