Abstract: To research the alkali resistance and durability of glass-fiber mesh cloth located in glass-fiber reinforced cement formwork during the service life,the traditional accelerated ageing method for glass fiber reinforced cement (GRC) and the NaOH Solution Immersion Method for glass-fiber cloth are adopted.Meanwhile,some contrast tests,whose specimens were immersed in water at room temperature,were conducted The alkali erosion effect of Ca(OH)₂ on glass-fiber in the formwork due to cement hydration of concrete is analyzed by contrasting the changing trends of strength and the strength retention rate of specimens after immersion in different solutions.According to the experiment results,the decline mechanism of long-term behavior of glass-fiber in cement-base material is discussed.Researches indicate that the probability of failure due to durability is very low during 50 years of service life specified by China Structure Design Code.