The invention relates to a pulsed-jet longitudinal impactor. The lower end of a pump upper cover and the upper end of a pump outer cover are connected through a thread, the lower end of the pump upper cover is connected with a central rotor, the upper end of a pump middle shaft is provided with a thread, and the pump middle shaft is fixed at the lower end of the central rotor and sits on a lower cover plate through a boss; the lower cover plate is fixed inside the lower end of the pump outer cover and fixes the central rotor and the pump middle shaft inside the pump outer cover at the same time, the pump outer cover is fixed inside a main pup joint by a fixing cover nut, a valve is fixed at the lower end of the pump middle shaft, and an upper valve plate is fixed inside the valve through a fixing bolt; a lower valve plate is fixed at the upper end of an impact valve which is provided with a thread, the impact valve is in threaded connection with an impact joint which is fixed inside a hexagonal sleeve, the upper portion of the main pup joint is connected with an upper drill column while the lower portion of the same is connected with the hexagonal sleeve, and the impact valve is fixed above the hexagonal sleeve and provided with a passageway inside. The pulsed-jet longitudinal impactor is few in middle structure, low in energy consumption, large in impact force and long in service life.