The invention provides a reinforced concrete pile head shearing and crushing device which comprises pile head scissor crushing arms, scissor arm fixed support large arms, a support working disc, a dynamic and hydraulic jack, a mechanical connecting piece, a dynamic and hydraulic jack fixed column, scissor arm top end fixed bolts and a scissor arm fixed supporting point bolt, wherein one end of the dynamic and hydraulic jack is connected with the dynamic and hydraulic jack fixed column, and the other end of the dynamic and hydraulic jack is connected with the scissor arm top fixed bolts of the pile head scissor crushing arms; the dynamic and hydraulic jack fixed column is fixedly arranged on the support working disc; the mechanical connecting piece is arranged on the center of the support working disc and is connected with the top end of a large arm of an excavating machine; the four pile head scissor crushing arms are respectively arranged on the support working disc and are symmetrically and uniformly arranged; a hydraulic system of the excavating machine is connected with the dynamic and hydraulic jack and is used for supplying power to the dynamic and hydraulic jack. Finished products of materials used in the device can be purchased from the market, and the device is simple in overall structure and free from special structural requirement.