The invention provides a broadband directional millimeter-wave antenna, which comprises a first dielectric substrate, a second dielectric substrate, a third dielectric substrate, a coplanar feed transmission line, a first ground plane, a second ground plane, a parasitic element, a first C-shaped reflecting surface, a second C-shaped reflecting surface, a bottom reflecting plate and a rabbit-shapedmain radiating element, wherein the first C-shaped reflecting surface and the second C-shaped reflecting surface arranged on the dielectric substrates on two left and right folded side surfaces and the bottom reflecting plate of the antenna form a closed cavity structure; the coplanar feed transmission line is connected with an inner conductor of a connector; and an outer conductor of the connector is connected with the ground planes. According to the broadband directional millimeter-wave antenna provided by the invention, the broadband and directional millimeter-wave antenna design is achieved by adopting a coplanar line feed structure, a structural design of a closed cavity formed between the folded dielectric substrates and the bottom reflecting plate and the design of a gap coupling structure between the rabbit-shaped main radiating element and the parasitic radiating element.