Disclosed is a key for a high voltage transformer substation switch cabinet. The key for the high voltage transformer substation switch cabinet is characterized in that the key comprises a key body and a rotation handle; a thread corresponding to a switch cabinet door lock is arranged in the front end of the key body; a hexagonal prism is arranged at the tail end of the key body, and the specification of the hexagonal prism corresponds to that of a hexagonal connector of an electric screw driver; a sliding mounting groove is formed in the top end of the hexagonal prism, and card lock mounting concave points are arranged on the two sides of the inner wall of the sliding mounting groove; the rotation handle is in a long bar shape, a sliding mounting block is arranged in the middle of the rotation handle, and the shape of the sliding mounting block corresponds to that of the sliding mounting groove; card lock mounting convex points are arranged on the two sides of the sliding mounting block, and the card lock mounting convex points are connected through an elastic component.