Abstract: There is severe high-temperature corrosion on the water-cooled walls of the 660 MW level front and rear wall opposed combustion boiler in a certain power plant. The water-cooled walls on the left and right sides are severely corroded and thinned, with large areas of coal powder brushing against the walls and uneven oxygen content in the tail flue gas. A series of combustion optimization strategies have been provided around the boiler, including the powder production system, combustion system, and air distribution system. After optimization, the concentration of reducing atmosphere CO on the left wall water-cooled wall decreased from 11.63% to 1.84%, and the concentration of reducing atmosphere CO on the right wall water-cooled wall decreased from 13.72% to 1.92%; The unevenness of oxygen content and CO concentration in the tail flue has been significantly improved. After adopting the above optimization strategies, the high-temperature corrosion of the water-cooled wall on the side wall of the boiler was effectively improved.