Electrosurgical instrument with joint seal

An electrosurgical instrument (10) with two branches (11, 12) that are pivotably supported at each other by means of a pivot joint (13) is disclosed. The pivot joint (13) has a support pin (34) and a support cavity (37). The support pin (34) is particularly torque-proof connected with one of the branches (11) or (12) and rotatably supported in the support cavity (37) of the respective other branch (12) or (11). Between the branches (11, 12) a seal (45) is provided that sealingly abuts at the two branches (11, 12) and that surrounds the support pin (34) completely in the circumferential direction. Preferably, the support pin (34) is sealingly connected with the respective branch (11, 12) at its axial ends. In doing so, entering of contaminants in the area between the support pin (34) and the support cavity (37) from all sides or access possibilities is inhibited.