A multiband antenna structure includes a matching portion, a first radiator, and a second radiator. The first radiator and the second radiator extend from a first edge of the matching portion. The second radiator and the matching portion resonate a first mode. The first radiator and the matching portion resonate a second mode. The slot, the first radiator, and the matching portion resonate a third mode. The second radiator includes a first connection section, a second connection section, a third connection section, and a fourth connection section. The first connection section is perpendicularly connected to a first end of the first edge. The second connection section is perpendicularly connected to the first connection section and extends parallel to the first edge. The third connection section is parallel to the first connection section. The fourth connection section is parallel to the second connection section.