The invention discloses a broadband one-way voice channel comprising an upper surface and a lower surface parallel to each other. A first reflector in the shape of an isosceles right-angled triangle is mounted on the upper surface. A second reflector in the shape of an isosceles right-angled triangle is mounted on the lower surface. The right-angle sides of the first and second reflectors are located on the upper surface and the lower surface, respectively; extension lines of hypotenuses of the first and second reflectors intersect; the upper surface and the lower surface are both provide with acoustic meta-surfaces, respectively. The broadband one-way voice channel has the advantages that reflecting paths of the first and second reflectors are simply utilized, super-thinness of the meta-surfaces and the abnormal reflection function are ingeniously utilized, full passage is allowed for acoustic beams under geometrically forward incidence, the acoustic beams under reverse incidence are fully reflected, and efficient one-way propagation is finally achieved; a barrier-free passage is formed between the first reflector and the second reflector, allowing fluid or a large object to pass through the barrier-free passage.