An antenna structure includes a metal housing, a first radiator, and an isolating portion. The metal housing includes a front frame, a backboard, and a side frame. The side frame is positioned between the front frame and the backboard. The side frame defines a slot and the front frame defines a gap. The gap communicates with the slot and extends across the front frame. The metal housing is divided into at least a long portion and a short portion by the slot and the gap. The first radiator is positioned adjacent to the short portion. The isolating portion is connected to the first radiator to improve isolation between the short portion and the first radiator.