A high alkali reactive aggregate zeolitization perlite was used to test the long term effectiveness of LiOH in inhibiting alkali silica reaction.In this paper,the rigorous conditions were designed that the mortar bars had been cured at 80℃ for 3 years after autoclaved 24 hours at 150℃.Under this condition,LiOH was able to inhibit the alkali silica reaction long term effectiveness.Not only the relationship between the molar ratio of n(Li)/(Na) and the alkali contents in systems was established, but also the governing mechanism of such effects was also studied by SEM. A high alkali reactive aggregate zeolitization perlite was used to test the long term effectiveness of LiOH in inhibiting alkali silica reaction.In this paper, the rigorous conditions were designed that the mortar bars had been cured at 80 ° C. for 3 years after autoclaved 24 hours at 150 ℃ .Under this condition, LiOH was able to inhibit the alkali silica reaction long term effectiveness. Not only the relationship between the molar ratio of n (Li) / (Na) and the alkali contents in systems was established, but also the governing mechanism of such effects was also studied by SEM.