Abstract: A three-dimensional ultra-thin artificial structure with strong directivity is proposed in this paper. The structure contains a central spiral structure and HR groove arrays which are engraved on the upper and lower sides of the structure. The central spiral structure reduces the thickness of the structure to make the overall structure thickness only one-tenth of the incident wavelength, extend the propagation distance of sound waves, and achieve F-P resonance at low frequencies. The HR groove arrays on both sides convert the scattered acoustic waves into surface acoustic waves bounding to the surface of the structure. The collimated emission of the acoustic waves is realized by coupling of the surface acoustic waves and the transmitted acoustic waves generated by the F-P resonance. The simulation results prove that the transmission distance of the collimated acoustic beam in the free sound field exceeds 15 times of the incident wavelength. The three-dimensional device achieves high-directional acoustic radiation in the deep sub-wavelength scale, and it is expected to have practical application values in noise control and electroacoustic design, etc.