A transparent display device attached to a predetermined product, displaying article information in the product, advertisement, etc. is disclosed. The transparent display device comprises a frame including an opening; a transparent display panel arranged at the opening; and a control module arranged in an area of the frame to control the transparent display panel, wherein the frame in which the transparent display panel and the control module are arranged is provided to cover a front surface of a predetermined product so as to form a door unit of the predetermined product, and is rotatably moved when the inside of the predetermined product is opened and closed.