A dual-band antenna for use in a wireless network device comprises first, second, and third radiators. The first and second radiators are connected by a stand portion. The second radiator is a generally C-shaped plate having a connecting section and a free-end portion. A ground end and an input end are provided at predetermined positions of the connecting section and are respectively and electrically connected to a grounding portion and a control circuit of a substrate. The free-end portion overlaps with the orthogonal projection of the first radiator and is parallel to the first radiator. The third radiator is electrically connected to the second radiator via a conductive post and is parallel to the second radiator. The second and third radiators are provided on the substrate while the first radiator is provided outside the substrate. The first, second, and third radiators are parallel to and spaced apart from one another.