The invention discloses an active intentional gesture action detection device. The device comprises an electromyographic signal obtaining device, an electroencephalogram signal obtaining device, a brain muscle signal acquisition device and a brain muscle signal processing device, wherein the electromyographic signal obtaining device is used for obtaining a gesture action electromyographic signal of an operator, and comprises a plurality of electromyographic electrodes which are arranged on the forearms of the operator in a ring-shaped array manner; the electroencephalogram signal obtaining device is used for obtaining an electroencephalogram signal of the operator, and comprises three claw-type dry electrodes in a right ear lobe A2 area, a right forehead Fp2 area and a right vertex center C4 area; the brain muscle signal acquisition device is used for acquiring the gesture action electromyographic signal and the electroencephalogram signal; and the brain muscle signal processing device is used for processing the acquired gesture action electromyographic signal and electroencephalogram signal, and judging whether gesture action actions of the operator are intentional actions or unintentional actions, active actions or passive actions. The invention furthermore discloses an active intentional gesture action detection method. The active intentional gesture action detection device and method have the beneficial effects of detecting whether the operators have intentional subjective gestures and improving the reliability of gesture interaction control.