A flexible electronic device includes a base substrate and first and second lines disposed thereon. The first and second lines extend in a first direction and are arranged in a second direction. Each of the first and second lines includes a first conductive layer including first and second portions alternately disposed with each other, and second conductive layers respectively overlapped with the first portions in a third direction substantially perpendicular to the first and second directions. The second conductive layer is not overlapped with the second portions of the first conductive layer in the third direction. The first and second conductive layers have a first modulus and a second modulus, respectively. A first width in the second direction of each of the first portions is smaller than a second width in the second direction of each of the second portions.