Abstract: The high temperature corrosion behavior of S30432 steel pipe was studied and analyzed by microstructure analysis, energy spectrum composition analysis and mechanical properties. The results showed that the reason for the blasting of the pipe sample was the effect of high temperature corrosion, the effective thickness of the pipe wall was reduced, and the structure of the blasting pipe was aging. The high-temperature corrosion layer was divided into two layers, the outer layer was the corrosion product layer, and the inner layer was the corrosion-affected zone between the matrix, holes and micro-cracks. Compared with the laboratory simulated environment, the in-service S30432 steel pipe was affected by factors such as coking on the outer wall and flue gas scouring, forming dense alternating corrosion products, which intensifies the loss of effective thickness of the pipe wall. For units burning high sulfur coal and high ash coal, it was necessary to strengthen the supervision and inspection of the corrosion of heating surface pipes.