The invention relates to a capacitor bank grounding device for a high-voltage assembling capacitor bank, which belongs to a repair and maintenance tool for high-voltage transmission equipment. The capacitor bank grounding device comprises an insulating operating rod; a conducting connecting hook is connected with the front end of the insulating operating rod; the conducting connecting hook is connected with a grounding grip holder through a grounding wire; the insulating operating rod is connected with the conducting connecting hook through a connector; the lower end of the connector is connected with the insulating operating rod; the upper end of the connector is connected with the conducting connecting hook through a stud shaft; and the conducting connecting hook can be rotated by taking the stud shaft as a rotating shaft and can be positioned and fixed in different angular positions through a nut. The device has the advantages that the structure is simple, the operation is convenient, and the device can perform electric discharge on a single capacitor in a whole capacitor bank, thereby greatly reducing the power off time in the examine and repair preparation process.