In order to reduce the oxidation and decarburization caused by high temperature in the course of the heat treatment of metal materials, an environment-friendly coating consisting of glass powder and red mud as the main raw materials is applied. It is brushed on the workpiece surface, heated in the box-type resistance furnace.The high temperature oxidation weight gain and the depth of decarburization between naked steel and coating steel are studied using weight gain method and metallographic method. The impact of the coating to reduce oxidation loss and the main properties of coating are analyzed. The result shows that processing properties of the glass-based coating are excellent:it has no crack at high temperature, distributes uniformly on the workpiece surface and can be self-spalling after quenching. It effectively prevents the workpiece from oxidation and decarburization at 800-1100 . The coating is of low cost and easy to use.