An antenna structure includes a first signal source, a second signal source, a first radiator, a second radiator, a third radiator, a first circuit, and a second circuit. The first signal source is used to generate a first wireless signal, and the second signal source is used to generate a second wireless signal. The first radiator is coupled to the first signal source to receive the first wireless signal, and the second radiator is coupled to the second signal source to receive the second wireless signal. The first circuit has a first end coupled to the third radiator and a second end coupled to the first radiator or the first signal source. The second circuit has a first end coupled to the third radiator and a second end coupled to the second radiator or the second signal source.