A flexible display device includes: a flexible substrate including a bending area; an insulating layer formed on the flexible substrate and including at least one cutout formed to correspond to the bending area; and a plurality of wires formed along a surface shape of the insulating layer in the bending area. The at least one cutout may include an inclined lateral wall, and a width of the inclined lateral wall may be equal to or greater than a depth of the cutout.