The utility model relates to the technical field of machinery, specifically a large -scale transformer box installs and removes device along bolt fast, its characterized in that is equipped with boltsupport and nut bracket, bolt support and nut bracket are by last extension board, lower extension board, left side board and right side board are formed by connecting, the last extension board of bolt support has bolt electric jack, be equipped with the bolt trepanning on bolt electric jack's the pneumatic cylinder, be equipped with the spout that is parallel to each other on bolt support and thenut bracket respectively, the supporting steel plate is connected with bolt support and nut bracket through slider and spout, one side that the supporting steel plate is located the bolt support is equipped with the rotating electrical machines, be equipped with nut socket on the rotation axis, one side that the supporting steel plate is located nut bracket is equipped with nut electric jack, nutelectric jack's pneumatic cylinder is connected with the fixed plate, the fixed plate is connected with nut bracket, the utility model discloses can install and remove large -scale transformer box along bolt automatically to ensure that the atress is even on the case edge everywhere, the installation is demolishd efficiently, labour saving and time saving.