A surgical instrument has an interlocking function and includes an end effector, an elongated portion and a handle portion. Two ends of the elongated portion are respectively connected to the end effector and the handle portion. The handle portion includes a handle housing, a rotatable knob arranged on a distal portion of the handle portion and operatively to be reciprocated along the longitudinal direction of the elongated portion, and a locking assembly including at least one slide member and a lockout gear. The slide member is arranged between the rotatable knob and the handle housing, and axially fixed with the rotatable knob so as to be reciprocated with the rotatable head for being operatively engaged with the slide member. The slide member is circumferentially fixed with the handle portion, and the lockout gear is rigidly mounted at a proximal portion of the elongated portion. The safety of the surgical instrument may be improved due to high structural stability and high stability between components.
