The invention provides a magnet-based torsion percussion boring tool.. The magnet-based torsion percussion boring tool mainly consists of an upper joint, a falling-proof nut, a falling-proof baffle plate, a supporting blocking ring, a casing, a worm wheel, hammer body fixing cavities, percussion hammers, splines, bore bit joints, a fixing cavity baffle plate, magnets, a supporting cylinder, a transmission shaft and a falling-proof pull rod, wherein the casing is connected with the bore bit joints through the splines; the casing is in threaded connection with the upper joint. When the magnet-based torsion percussion boring tool works, drilling fluids drive the worm wheel to rotate, the worm wheel transmits kinetic energy to a lower end hammer body fixing cavity through the transmission shaft, the percussion hammers fixed in the cavities continuously hit a corresponding striking bearing block on the casing during rotating, and percussion energy is transmitted to a bore bit for rock breaking through the bore bit joints. The magnets are used in a percussion assembly of the torsion percussion tool disclosed by the invention, and are fixed to the end surfaces of the inner sides of the percussion hammers. When the percussion hammers hit the striking bearing block, under the effect of percussion force, the hammer bodies can move to the inner side of the fixing cavity, and can be reset by repulsion force of the magnets after percussion is completed. According to the magnet-based torsion percussion boring tool disclosed by the invention, high-frequency torsion percussion force for rock breaking can be formed, and the stick-slip vibration of the bore bit is reduced.