An antenna structure includes a ground element, a feeding radiation element, a first radiation element, a second radiation element, a shorting radiation element, a third radiation element, and a fourth radiation element. The feeding radiation element has a feeding point. The first radiation element is coupled to the feeding radiation element. The second radiation element is coupled to the feeding radiation element. The second radiation element and the first radiation element substantially extend in opposite directions. The feeding radiation element is further coupled through the shorting radiation element to the ground element. The third radiation element is coupled to the ground element. The third radiation element is adjacent to the first radiation element. The fourth radiation element is coupled to the ground element. The fourth radiation element is adjacent to the second radiation element.