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Based on the characteristics of morphology and hardness distribution of scapharca shell surface, a bio inspired model of the material coupled with pattern was proposed. The major and minor relationship and optimal combination of the main factors which affected the erosion resistance of the bio inspired surface was obtained through experiments. Erosion resistant tests were carried out under the following test conditions: abrasive was the compound of silica sand of 80~140 mesh size and water; wear time was 30h; and the rotating speed of 1400r/min. Compared with the smooth testing samples, the erosion resistance of the smooth testing sample of alloying with laser, the smooth one of laser hardening, the bio inspired model with the non smooth pattern and the bio inspired model of the material coupled with pattern can improve the anti erosion performance of the samples surface. The bio inspired model of the material coupled with pattern was the best one among all the testing samples. The order of major and minor factors affecting the relative wear rate of samples was laser hardening, amplitude, periodic and the stripe direction. Results showed that the testing sample with optimal anti erosion performance was the one with laser surface strengthening, amplitude of 3mm, period of 10mm and the direction of the stripes normal to the flow direction of particles.