Recently, many kinds of waste-to-energy combustion systems have been operated to minimize harmful emissions such as dioxines and NOx. Corrosion environments in these plants have become severe and complex. In order to realize high efficiency and low maintenance for these plants, the development of low cost alloys and suitable application processes are important technologies. In the past ten years, many kinds of corrosion-resistant material systems were tested and applied to actual boilers. For example, high Cr, high Mo nickel-base alloys and high Cr, high Si Fe-Ni alloy tubing products are applied in actual plants. Furthermore, coating systems such as thermal spray, weld overlay, etc., have been developed and applied to advanced waste-to-energy boilers. Also, mechanisms maintaining the corrosion resistance of alloys have gradually become clear by detailed investigation in actual plants and in he laboratory. This presentation shows recent progress in corrosion resistant alloys and coating for advanced waste-to-energy boilers.