A cover window is proposed. Particularly, a flexible cover window having improved visibility for a flexible display is proposed, the flexible cover window including: a first window made of glass and provided on an upper part of a first surface of the flexible display; a second window made of glass and provided on an upper part of a second surface of the flexible display; and a folding part provided between the first window and the second window by corresponding to a folding area of the display and filled with a transparent resin material, wherein a transparent resin layer is provided on a total surface of each of the first window and the second window by continuing to the folding part filled with the transparent resin material.