A package structure of flexible display device includes a flexible opto-electronic display panel, a first barrier layer and a second barrier layer. The flexible opto-electronic display panel includes a backplane, a flexible frontplane, and a display media layer. The display media layer is disposed between the flexible frontplane and the backplane, where the display media layer is substantially corresponding to a display region of the backplane, and at least one side of the display media layer aligns with one corresponding side of the backplane. The first barrier layer is disposed on a first surface of the flexible frontplane, where the flexible frontplane, the display media layer and the first barrier layer expose a bonding region of the backplane. The second barrier layer is disposed on a second surface of the backplane.