A flexible display device includes a TFT array substrate, a flexible printed circuit board, a front panel laminate, a first protection sheet having a through hole, and waterproof glue. The flexible printed circuit board is disposed on an edge of a first surface of the TFT array substrate, and extends outward from the edge of the first surface. The front panel laminate is located on the first surface of the TFT array substrate. The first protection sheet covers the front panel laminate, the first surface of the TFT array substrate, and the flexible printed circuit board. A portion of the flexible printed circuit board and a portion of the TFT array substrate are located in the through hole. The waterproof glue is located in the through hole and covers the portion of the flexible printed circuit board and the portion of the TFT array substrate.