A mobile communication device includes a ground plane, a dielectric substrate, and an antenna. The antenna is disposed on one surface of the dielectric substrate and includes a radiating portion, a feeding portion, and a shorting portion. The radiating portion includes a first radiating portion and a second radiating portion. The first radiating portion has at least one bending. One end of the first radiating portion is left open. The second radiating portion is a shunt metal strip. Both ends of the second radiating portion are electrically connected to the first radiating portion such that the second radiating portion forms a closed loop with a segment of the first radiating portion. The feeding portion couples the electromagnetic energy to the radiating portion through a coupling gap, and one end of the feeding portion is the antenna's feeding point. One end of the shorting portion is electrically connected to the radiating portion, and the other end of the shorting portion is electrically connected to the ground plane.