A mouse with a screen saver control function is provided. The mouse includes a left button, a right button, a scroll button, a screen saver control button, a memory unit, and a micro-processing unit. The memory unit stores a simulation program. When receiving a signal from the screen saver control button, the micro-processing unit runs the simulation program of the memory unit, and generates simulated input signals to a computer connected thereto, and thus to prevent the computer from running a screen saver program. Utilizing the mouse, a computer user can control a screen saver of the computer momentarily, without resetting a duration of initiating the screen saver program. Therefore, the mouse is very convenient for the computer user to control the computer.