Objective In order to avoid similar corrosion failure accidents, the failure analysis of the heat exchanger tube bundle leakage occurred in the three-effect continuous evaporation and crystallization device was carried out to find the cause of failure. Methods The macro morphology of corrosion and the location of corrosion were determined by using macro detection method. The corrosion resistance of TA10 alloy in tube and shell was determined by full immersion test. Microscopic morphology of surface corrosion was observed by SEM. Finally, the components of the corrosion products were determined by the methods of EDS and XRD. Results In the heat exchanger, the baffle plate was corroded, and irregular flaking occurred to its metal surface. Severe corrosion occurred outside the tube bundle, and the corrosion of the tube exit only occurred in the Weld line; The corrosion behavior of TA10 alloy did not happen under the condition of the tube pass, but it happened under the condition of the shell pass. The corrosion surface had a multi-layer structure, and the surface shape was irregular, The corrosion product was TiH2. Conclusion TA10 alloy could not achieve good corrosion resistance in shell side. Under the existing technological conditions, the generation of the dew point led to generation of a high concentration of hydrochloric acid outside the heat exchanger tube, which would react with the TA10 alloy resulting in severe hydrogen absorption and consequently hydrogen induced cracking and absorbing hydrogen embrittlement. With the erosion of gas, a large area of metal peeling phenomenon appeared. The crevice corrosion occurred in the connecting place of the heat exchange tube and the tube plate, and Titanium was dissolved as an anode in the crevice. Finally, some suggestions were put forward to prevent corrosion.