The invention relates to a cutting off device, in particular to a fast cutting off device for hardware parts. The invention solves the technical problem of providing a cutting device for a covering steel plate for production of a circuit board, which is light and handy, fast in cutting off and good in cutting off effect. In order to solve the technical problem above, the invention provides such a fast cutting off device for hardware parts, which comprises a bottom plate, first guide rods, first guide covers, a moving rod, a lifting device, a top plate, a moving device, a lifting rod, a mounting rod, a second motor, a blade, first supports, and the like; the first guide rods are symmetrically welded on the left side and the right side of the top of the bottom plate, the top plate is welded on the top ends of the two first guide rods, the middle of the bottom of the top plate is provided with the lifting device, and the bottom of the lifting device is connected to the lifting rod. By controlling the lifting device to move up and down, the blade is controlled in an optimal position, such that the cutting off effect is better, and by driving the blade to move left and right through the moving device, the cutting off is more thorough.