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Dolphin’s special skin structure has characteristics of drag reduction, by mimicking this structure, a kind of bionic coupling functional surface which has practical engineering application value was designed. It was applied on the surface of a centrifugal pump impeller to investigate the efficiency enhancement of the pump through contrast experimental method. The experimental results showed that the pump efficiency was improved by 3% by using this kind of bionic coupling functional surface. The hardness of surface material had influence on the pump efficiency. The mechanism of efficiency enhancement of bionic coupling functional surface was the coupling deformation between elastic surface material and bionic structure on the basal material, which can decrease the drag of impeller surface, absorb some energy and effectively reduce the turbulent kinetic energy of the inlet and outlet of impeller, thus, the hydraulic loss would be decreased.