The invention discloses a valve core stroke limiter of a reversing valve of a hydraulic excavator. The stroke limiter comprises a valve core screw stem, a combined sealing washer, a valve body, a right-angled joint, an O-shaped rubber seal ring, a hinge bolt, a locking nut and the like, wherein a threaded end of the hinge bolt is arranged on a pilot oil port of a hydraulic reversing valve; one end of the right-angled joint is connected with a pilot control rubber pipe assembly to ensure that a pilot oil passage is normally communicated with the hydraulic reversing valve; the locking nut is screwed off and placed at a hexagonal clamping position with an inner hexagon spanner, and the valve core screw stem is slowly screwed in or out until the working speed of a hydraulic actuating element meets or approaches a target valve; and the locking nut is locked to finish the entire debugging process. The stroke limiter has the advantages of simple structure, low manufacturing cost, stable performance, long service life, simplicity of operation, wide application and the like, can be repeatedly used and adjusted and can be used in valve plates of other hydraulic reversing valves to be adjusted.