Abstract: The directional emission device of ultrasonic beams is constructed based on the ultrathin planar ultrasonic metasurface. The high efficiency and the high robustness of directional emission effects of acoustic beams with different structural unit configurations are demonstrated by the finite element simulation. The designed metasurface is arranged by the periodic structural units, and the performance of acoustic directional emission can be effectively maintained in the case of the structural units with random distribution shapes or geometric defects. The directional emission device of ultrasonic beams based on ultrasonic metasurface has the advantages of simple design, high directional accuracy, strong flexibility and applicability, and has a wide application prospect in the fields of industrial non-destructive testing, underwater detection and medical ultrasound projects.