Abstract: The causes of titanium alloy valve corrosion were analyzed by means of chemical composition, mechanical property analysis, metallographic structure observation, macro and micro morphology observation and corrosion products analysis. The results showed that the composition and structure of globe valve disc could meet the design requirements. Corrosion on sealing surface of globe valve disc was caused by the combined action of decomposition corrosion, erosion and crevice corrosion. Large amount of seawater and sediment in pipelines could promote the appearance of crevices and increase the scouring intensity, which would accelerate the corrosion process.