The invention provides a mobile communication device which includes a substrate, a metal frame, a feed-in part and a parasitic part. The substrate includes a grounding face and a headroom area. The metal frame surrounds the periphery of the substrate and includes a plurality of gaps so as to form a first frame element and a second frame element, which are mutually separated. The first frame element is electrically connected to the grounding face. The feed-in part and the parasitic part are located in the headroom area. A first end of the feed-in part is used for receiving feed-in signals and a second end of the feed-in part is an open circuit. The parasitic part is electrically connected with the second frame element and the grounding face. The mobile communication device forms an annular antenna through the feed-in part, the second frame element and the parasitic part.