A flexible display panel and a method for preparing thereof are provided. The method for preparing the flexible display panel includes providing a glass substrate and applying a thermosetting polymer on the glass substrate; curing the thermosetting polymer thereon into a solid film by baking; removing the solid film on a surface of a bonding region to expose a surface of the glass substrate underneath; forming a buffer layer on a surface of the solid film and the surface of the glass substrate from which the solid film has been removed; forming a metal layer on the buffer layer; forming a solder pad and metal wiring in the bonding region of the metal layer; attaching a chip to the solder pad of the bonding region after finishing bonding and sawing of a panel unit; and removing the glass substrate outside the bonding region and a transition region.