Erosion wear exists widely in industries including ship, machinery, metallurgy, energy, construction materials, aviation and aerospace, and has become one of the most serious issues for the material damage or equipment failure. Surface engineering techniques, especially the nano–structured coating, have become the most effective solutions for the erosion problems. WC-CoCr cermet coatings have drawn much attention in the research of the erosion resistant coating materials in recent years as their outstanding wear resistance. The multimodal WC-CoCr coatings deposited by High Velocity Oxygen Fuel spraying (HVOF) are expected to obtain dense structure and excellent erosion wear resistance. In this study conventional and multimodal WC-10Co4Cr cermet coatings were sprayed respectively by High Velocity Oxygen Gas Fuel spraying (HVOGF) and High Velocity Oxygen Liquid Fuel spraying (HVOLF), and the coating structures were investigated by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Porosity, microhardness and fracture toughness of the coatings were measured. Erosion resistance of the coatings to solid sand was tested and influence of WC size and HVOF process on the failure mechanisms of WC-10Co4Cr coatings were explored. Results show that the WC-10Co4Cr coatings deposited by HVOLF are mainly composed of WC, amorphous CoCr, and a small amount of W2C, no obvious WC decarburization can be detected. The mechanical properties of WC-10Co4Cr coatings deposited by HVOLF are much more superior to those deposited by HVOGF. Multimodal WC-10Co4Cr coating deposited by HVOLF possesses the highest microhardness and fracture toughness, the lowest porosity, the most excellent resistance to sand solid erosion wear. The solid sand erosion resistance of multimodal WC-10Co4Cr coating deposited by HVOLF was enhanced above 15% and 40% respectively than conventional coatings deposited by same prosess at 30° and 90° impact angles, and was approximately 3 times higher than that of multimodal coatings deposited by HVOGF at same testing conditions. The research results have provided important reference for WC-CoCr anti-erosion coating design and optimization of HVOF process.