A built-in antenna for an electronic device is provided. The built-in antenna includes a substrate, a 1st antenna radiator with at least two radiating portions, a 2nd antenna radiator, and a switching means. The substrate has a conductive area and a non-conductive area. The 2nd antenna radiator is arranged within the non-conductive area of the substrate and fed by a Radio Frequency (RF) end of the substrate. The 2nd antenna radiator is configured to operate at a band different from at least one operating band of the 1st antenna radiator, and is fed by the RF end in a position adjacent the 1st antenna radiator. The switching means switches to selectively feed the 1st antenna radiator and the 2nd antenna radiator.