1. An electronic device comprising:a housing comprising a front plate, a rear plate spaced apart from the front plate and facing the front plate, and a side structure connected to the front plate and the rear plate, wherein:
the front plate comprises a first flat portion that faces in a first direction, and a first side face portion extending from an edge of the first flat portion toward the rear plate,
the rear plate comprises a second flat portion that faces in a second direction opposite to the first direction, and
when the front plate is viewed from above, the first flat portion and the first side face portion together form a rectangular shape comprising a first edge portion extending in a third direction perpendicular to the first direction and including a first length, and a second edge portion extending in a fourth direction perpendicular to the first direction and the third direction and including a second length longer than the first length;
a touch screen display that faces in the first direction and is coupled to the front plate, wherein the touch screen display comprises a first layer, a second layer, and a third layer, that are stacked on each other, and the first layer and second layer are disposed such that the first layer is closer to the front plate than the second layer, and the second layer and the third layer are disposed such that the second layer is closer to the front plate than the third layer, and when the rear plate is viewed from above, a part of the first layer protrudes from the second layer and a part of the second layer protrudes from the third layer in a region adjacent to a point where the first edge portion and the second edge portion meets each other;
a filler formed in the region; and
a processor electrically connected to the touch screen display.