Using the bionic coupling principle, the typical unit body is extracted, and the wear-resistant surface of nodular cast iron with better wear resistance can be obtained by laser melting technology. Through simulation, it is found that the stress concentration at the unit body and the stress reduction of the matrix appear on the bionic coupling surface. By compounding typical bionic structures and changing structural parameters, the stress magnitude and distribution of friction surface can be changed. The simulation research was carried out by using the software, and the following conclusions were drawn: The results show that for the straight line+involute composite bionic unit, when only the distance between straight lines is changed, the friction stress on the unit increases, while the friction stress on the substrate surface decreases, and the wear resistance of the material increases with the increase of the distance between straight lines. When the linear distance reaches 7mm, the friction stress on the substrate surface is the smallest and the wear resistance of the material is the best; When only the involute base circle radius is changed, the wear resistance of the material increases first and then decreases with the increase of involute base circle radius. When the radius of involute base circle reaches 0.5mm, the friction stress on the substrate surface is the smallest, and the wear resistance of the material is the best.