Abstract: A series of problems have cropped up in Dushanzi Petrochemical Company 50 kt/a sulfur recovery unit since the startup in 2009, which including the corrosion of stripper air cooler outlet pipe, the corrosion and leakage of air cooler, liquid sulfur jacket pipe, acid water pipe and cooling water pipe line, the flameout of tail gas incinerator, and the hydrocarbon-bearing in the acid gas, etc. The preventive measures aiming at above problems were developed. Through the analysis of the mechanism of all kinds of problems and the impact on the device, it was concluded that corrosion leakage was the most important factor which affected the long period operation of sulfur recovery unit, and preventing non-normal corrosion of the equipment and pipeline was the most important measure to ensure long term operation.