The invention discloses an outdoor high-voltage isolated switch which comprises a steel channel base (1), an insulator support column (2), a wire inlet plate (3), a knife switch, an arc protection device, a misoperation prevention mechanism and a wire outlet plate (8), wherein the knife switch comprises a knife plate (4), a locking device (5) and a static contact (7), the locking device (5) comprises a self-locking hook, a self-locking hook spring and a hook ring piece, the self-locking hook and the self-locking hook spring are arranged on the hook ring piece to form a self-locking pull hook, the wire inlet plate (3) is shaped as an L, a part, protruding upwards, of the wire inlet plate is taken as a movable contact and is in contact with the knife plate (7), the movable contact is provided with a through hole, and when the switch is in a closing state, the through hole clamps the self-locking hook of the locking device (5). The outdoor high-voltage isolated switch has the advantages of a simple structure, safety, reliability, no change on production process, low processing cost and a long service life, and the problems of the influence on conductive efficiency due to a crack generated between the movable contact and the wire inlet plate and the like can be effectively solved.