An antenna module suited for a portable electronic device is provided. The antenna module includes a heat dissipation unit, a first antenna and a second antenna. The heat dissipation unit contacts a heat source of the portable electronic device. The first antenna and the second antenna are disposed at different side portions of the heat dissipation unit. The heat dissipation unit has a slot with at least one bending portion. An orthogonal projection of at least one of the first antenna and the second antenna on a projection plane of the heat dissipation unit is partly overlapped with an orthogonal projection of the slot on the projection plane.