A mobile communication device for operating in LTE and WWAN bands is provided in the invention. The mobile communication device includes a system circuit board and an antenna. The system circuit board includes a system ground plane. The antenna includes: an antenna substrate, substantially parallel to the system ground plane; a first radiation element, disposed on the antenna substrate; a second radiation element, disposed on the antenna substrate; an antenna ground plane, disposed on the antenna substrate, and coupled to the system ground plane; and a transmission line, disposed on the antenna substrate, coupled to the first and second radiation elements, and having a feed point. The mobile communication device is further configured to accommodate a data transmission component.