An electronic device is provided. The electronic device includes a first housing, a second housing, a flexible display, a printed circuit board, an antenna radiator, and a flexible printed circuit board. The second housing slides in a first direction to be pulled out of the first housing and slides in a second direction opposite to the first direction to be pulled into the inside of the first housing. The flexible display is disposed in the first housing and the second housing. The printed circuit board is disposed in the second housing and may move according to sliding of the second housing. The antenna radiator is disposed on a side surface of the first housing. The flexible printed circuit board electrically connects the printed circuit board and the antenna radiator. The first housing includes a through hole formed in a side surface thereof, and at least a portion of the antenna radiator may be inserted via the through hole into the inside of the first housing. The antenna radiator may move on the side surface of the first housing according to sliding of the second housing.