To solve the problem that the life of a fire grate of an incinerator is deterionated, replacement cycle is shortened and the maintenance cost of the fire grate of the incinerator is increased because incineration temperature is raised for suppressing the generation of toxic substances at the incineration.

The fire grate has surfaces A and B exposed to a part functioning as an outlet of the air when the fire grate is mounted inside the furnace of the incinerator and the surfaces are cladded by welding with metals having superior high temperature corrosion resistance and oxydation resistance than those of fire grate casting metals. The fire grate is protected from surface oxidization by the cladding with welded metals and has an improved durability, the maintenance cost of the incinerator can be reduced by the prolonged replacement cycle of the fire grate, and the generation of toxic substances such as dioxins can be reduced by the capability of high temperature burning.