In order to construct a surgical instrument comprising a shaft, at least one tool pivoted at its end, a swivelling component pivoting about an axis of rotation and swivelling the tool between an open and a closed position and an actuating component moving the swivelling component about the axis of rotation and operable from the opposite end of the shaft to the tool so that the high closing forces required for the plastic deformation of objects can also be attained at the tool or tools without transferring excessive forces to the driving mechanism, it is proposed that the actuating component comprise an arm which is articulated on the swivelling component at a first joint and that, with the tool open, the arm lie obliquely to an axis of the swivelling component running perpendicularly to the axis of rotation through a first linkage point and, with the tool closed, substantially perpendicular to the axis of the swivelling component.