Grinding forces, protrusion height, grinding temperatures and wear of diamond grits have been studied in grinding cemented carbide YG8 with a single-layer vacuum brazed diamond wheel. The experiment results indicate that the primary wear progression of diamond grits in the whole grinding process follows the mode of whole diamonds, flat diamonds when grinding of the cemented carbide. The worn mechanism of the failure of diamond grits was discussed and possible solutions are recommended. The proportions of diamond conditions and the mean protrusion height of grains are more closely related to grinding forces and grinding temperatures. The grinding forces, force ratio and grinding temperatures decreased with the increasing proportions of whole crystal and the decreasing mean protrusion height of diamond grits, and the tangential and normal force components increased with the gradual wear of the brazed diamond wheel during a long-time grinding process. It shows great potential in improving thermal damage of cemented carbides by reduces grinding temperature with vacuum brazing diamond wheels.