Abstract: The corrosion of metal anode electrolytic tank seriously affects the safety of total equipment，and the yield and quality of chlor-alkali production.This study simulated the basic or acid condition of chlor-alkali production，and revealed the corrosion behavior of electrolytic tank and its influences by weight-loss method.The experimental results showed that in the chlor-alkali production environment，when the cell temperature was at 85~90 ℃，the catholyte NaOH mass fraction between 8%~12%，and the anode solution pH was below 4，the corrosion rate of the electrolytic tank was at the lowest.On this basis， a practicable method was put forward to protect electrolytic tank against corrosion.

Key words: chlor-alkali, metal anode electrolytic tank, corrosion, protection