HVOF thermal spraying tests were carried out for thermal spraying the coatings with two kinds of cermets powders,which are microstructured Sulzer Metco Diamalloy 2004 WC-12%Co powders and nanostructured WC-12%Co powders.The microstructures of the as-prepared WC-Co coatings were then characterized by using XRD analyzer and SEM The XRD results showed that the main phase in the nanostructured coatings is WC with a little W2C carbon deficient phase,and that means the thermal spraying parameters are well controlled in the process of HVOF thermal spraying.The mechanical properties of the two coatings were evaluated by microhardness test,bend test,cup test,tensile test and abrasive wear test.