A flexible electronic device including a flexible panel and an auxiliary layer is provided. The flexible panel has a plurality of operation portions, wherein a predetermined bending portion disposed between each adjacent two of the operation portions. The auxiliary layer is disposed on a surface of the flexible panel and at least located above the predetermined bending portion. The predetermined bending portion of the flexible panel may be bent in a first bending state for the auxiliary layer to be in contact with the predetermined bending portion, and a radius of curvature of the auxiliary layer is greater than a radius of curvature of the predetermined bending portion. The flexible electronic device has a first compressive stress region and a first tensile stress region, and a range of the first compressive stress region is greater than a range of the first tensile stress region.