A wireless communication device includes a metal cover and an antenna. The metal cover is formed with a slot. The antenna is disposed in the metal cover for resonating a radio-frequency signal via the slot, and includes a feed terminal, a radiator and a ground. The feed terminal is used for feeding the radio-frequency signal. The radiator includes a first arm electrically connected to the feed terminal and extended from the feed terminal along a first direction, and a second arm electrically connected to the first arm and extended from the first arm along a second direction, wherein the second arm is partially overlapped with a first edge of the slot.