The invention provides a dual-purpose insulating height adjustable stool, and relates to the technical field of high-voltage power supply. The dual-purpose insulating height adjustable stool comprises a flat plate I, a vertical plate and a flat plate II, and is characterized in that the flat plate I and the vertical plate are hinged, the flat plate II and the vertical plate are hinged, a positioning mechanism is arranged which enables a right-angle internal corner to be formed between the flat plate I and the vertical plate and enables a right-angle external corner to be formed between the flat plate II and the vertical plate, and four corners of the bottom part of the flat plate I and two corners of the rear part of the flat plate II are provided with movable supporting legs; the bottom surface of one or more of the flat plate I, the vertical plate and the flat plate II is provided with a travelling device; and the positioning mechanism is provided with limiting holes used for limiting when the flat plate I, the vertical plate and the flat plate II are located at the same plane. The dual-purpose insulating height adjustable stool is reasonable in structural design, simple and convenient in using method, and capable of effectively saving the space occupied by the height adjustable stool. Meanwhile, the dual-purpose insulating height adjustable stool further has a transportation effect, and improves the work efficiency. In addition, the dual-purpose insulating height adjustable stool ensures the personal safety of power workers, and has good social and economic benefits.