This study is focused on the investigation of the effect of substrate surface pretreatment on the interfacial bonding between a Ti6Al4V coating, prepared by supersonic laser deposition, and a substrate. Prior to the deposition, the substrate surface is pretreated by three different methods, namely polishing, grinding, and sand blasting. The phase composition and roughness of the substrate surface are analyzed using an X-ray diffractometer and a surface profilometer, respectively. An optical microscope is employed to analyze the interfacial bonding between the coating and substrate, while the bonding characteristics between the particles and substrates with different surface roughness, is numerically evaluated using a finite element model based on single particle impact. The results indicate that the coating detaches from the substrate treated by grinding owing to the formation of titanium-oxide ceramic phases on the substrate surface. However, the surface roughness of the polished substrate is lower than that of the sand blasted one, and thus, the coating/polished substrate interface is more tightly bonded. The numerical simulation results demonstrate that because of the undulating characteristics of the substrate surface, the particle/substrate interface shows inhomogeneous temperature and strain distributions, which prevent close bonding between the particles and substrates.