The instant disclosure provides an antenna structure including a substrate, a first radiation element, a second radiation element, a coupling element, a grounding element, and a feeding element. The first radiation element is disposed on the substrate, including a first radiation portion, a second radiation portion, and a feeding portion connected between the first radiation portion and the second radiation portion. The second radiation element is disposed on the substrate, including a third radiation portion and a coupling portion connected with the third radiation portion. A gap is formed between the first radiation portion and the third radiation portion. The coupling element is disposed on the substrate. The coupling element is separated from the coupling portion and coupling to the coupling portion. The grounding element is coupled with the coupling element. The feeding element is coupled with the feeding portion and the grounding element.