A system for controlling a robot by brain electrical signal, includes a screen, an electronic signal detection device, and a host computer. The screen shows a plurality of icons thereon, and the plurality of icons flashes at different frequencies. The electrical signal detection device detects brain electrical signal when one of the plurality of icons is stared. The host computer stores a plurality of personal reference parameters corresponding to the plurality of icons of the screen. The host computer processes the brain electrical signal to get parameters of use, and compares the parameters of use with the plurality of personal reference parameters to choose and execute the icon which is stared.
