An antenna module is provided. The antenna module includes a radiator, a feed pin, a ground element, a first parasitic arm, a second parasitic arm and an impedance matching unit. The radiator includes a first section and a second section, wherein an end of the first section is connected to the second section, and the first section is perpendicular to the second section. The feed pin is connected to another end of the first section. The first parasitic arm is parallel to the second section, wherein an end of first parasitic arm is connected to the ground element, and the first parasitic arm couples with the second section of the radiator. The impedance matching unit is connected to the second section and the ground element. The second parasitic arm is partially parallel to the first section, and the second parasitic arm couples with the first section of the radiator, and an end of the second parasitic arm is connected to the ground element.