An antenna structure, used for being fed with a signal, includes a grounding portion, a radiation portion, and a frequency adjusting portion. The radiation portion has a loop segment, a high frequency segment, and a low frequency segment. The loop segment has a feeding sub-segment adjacent to the grounding portion and used for being fed with the signal. The high and low frequency segments are extended from opposite ends of the loop segment away from each other. The frequency adjusting portion is connected to the loop segment and the grounding portion. A high frequency dual-path is formed from a feeding point of the feeding sub-segment and extends along the loop segment in two different directions to the high frequency segment. A low frequency dual-path is formed from the feeding point and extends along the loop segment in two different directions to the low frequency segment.