A mobile device includes a ground element, a metal frame, a feeding connection element, a first radiation element, a second radiation element, a capacitive element, a first shorting element, a secondshorting element, and a third shorting element. The first radiation element is coupled to the feeding connection element. The second radiation element includes a first portion and a second portion. The feeding connection element is coupled through the second radiation element to the metal frame. The capacitive element is coupled between the first portion and the second portion. The first shortingelement, the second shorting element, and the third shorting element are coupled between the metal frame and the ground element. An antenna structure is formed by the ground element, the metal frame,the feeding connection element, the first radiation element, the second radiation element, the capacitive element, the first shorting element, and the second shorting element.