A flexible display device includes a housing, a supporting plate, and a flexible panel. The housing has a central plate, a first wing plate, and a second wing plate, and the first and second wing plates are arranged on edges of the central plate, respectively. The supporting plate is on a surface of the housing, and the supporting plate is combined with the central plate and the first and second wing plates. The flexible panel is combined with the supporting plate. A flat state and a bending state of the flexible panel are provided according to states of the first and second wing plates with respect to the central plate.