An analytical study of high-temperature corrosive failure in a waste incineration plant was conducted using a new type EPMA equipped with a Schottky type field emission gun. For sample preparation, a cross-section polisher that uses an argon ion beam was applied. Both the element distribution through the alloy substrate to the scale and the chemical states of sub-micron sized corrosion products were revealed, leading to inferences about the corrosion mechanism.