A percussion tool comprises a cylinder 6 provided in a percussion tool body 1, and a piston 8 accommodated in the cylinder 6 and slidable in an axial direction of the cylinder pressure of pressurized air. A nail guide 10, provided at a front end of the percussion tool body 1, is formed into a hollow cylindrical shape capable of loading a nail 12 therein. A retaining region 15 is formed on an inner wall of the nail guide 10. A permanent magnet 19 is disposed in the retaining region 15 for magnetically holding a shaft of the nail 12 loaded in the nail guide 10. A stepdown region 14 is formed on the inner wall of the nail guide 10 inwardly than the retaining region 15 in an axial direction of the nail guide 10, so that the loaded nail 12 is aligned in parallel with a nail hitting direction. A slant surface 16 smoothly connects the stepdown region 4 to the retaining region 15. A driver blade 7, extending in the same direction as the nail hitting direction, has a base end connected to the piston 8 and a distal end acting as a hitting face 17 for hitting a head of the nail 12. A round surface is formed on a peripheral end of the hitting face 17, thereby permitting the driver blade 7 going out of a recessed portion 18, when the recessed portion. 18 is formed on the head of nail 12 during a hitting operation, without being locked in or engaged with the recessed portion 18.