The invention discloses a percussion 
drill. The percussion 
drill comprises a case; a supporting part and a 
high power density brushless motor erected on the supporting part are arranged in the case; a controller of the 
high power density brushless motor is arranged in the case; the 
high power density brushless motor comprises a rotor shaft rotationally arranged in the supporting part; a chuck of the percussion 
drill is fixed at one end of the rotor shaft; an 
impact movable gear is arranged at the other end, far from the chuck, of the rotor shaft; and an 
impact static gear, arranged corresponding to the 
impact movable gear, is arranged in the case. According to the percussion drill provided by the invention, the service life of the percussion drill is prolonged; the generation of carbon 
powder is avoided, and environmental 
pollution is avoided; and a transmission apparatus arranged in the case is avoided, so that the service life of the percussion drill is prolonged, the 
energy consumption is reduced, the output efficiency is improved, the 
noise and the vibration are reduced, the trouble in engagement installation of the transmission gears is avoided, the volume and the weight of the percussion drill are effectively reduced, and convenience is brought for the assembling of the percussion drill.