Abstract: An electronic device is provided. The electronic device includes a first electrical element, a second electrical element, and a rigid flexible printed circuit board electrically connecting the first electrical element and the second electrical element, wherein the rigid flexible printed circuit board includes at least one flexible portion including a first dielectric which has a first dielectric constant and is flexible, at least one rigid portion which extends from the flexible portion and includes a second dielectric which has a second dielectric constant and is less flexible than the first dielectric, a plurality of conductive patterns formed inside the first dielectric and the second dielectric, a plurality of conductive layers formed on the first dielectric and the second dielectric, and a plurality of conductive vias which are formed in the rigid portion and electrically connect the plurality of conductive layers or the plurality of conductive patterns.