The invention discloses a game device based on a brain-machine interface. The game device comprises an electrode, a brain electrical signal collecting box and a PC (personal computer), wherein the electrode is used for collecting original stimulated brain electrical signals generated when an operator opens and closes eyes; the brain electrical signal collecting box is used for carrying out the amplification, filtration and analog-digital conversion on the collected original stimulated brain electrical signals and transmitting the signals to the PC; and the PC is used for receiving digital signals sent by the brain electrical signal collecting box, carrying out filtration and energy average treatment, comparing with a threshold voltage and generating an impulse control command used for controlling the operation of a target in a game. According to the invention, the operator can regulate brain electrical signals through opening or closing the eyes so as to achieve the rapid and reliable real-time operation control of the game, and the game operation is simple; and the game device disclosed by the invention has the characteristics of high input impedance, high common-mode rejection ratio, low noise, low drifting and the like in the aspect of brain electrical signal collection.