Abstract: Three Pleurotus species,P.ostreatus,P.pulmonarius and P.djamor were cultivated in substrate containing 0%,2%,4% and 6% of hydrated lime respectively.The effect of hydrated lime addition on the mycelial growth,fruiting body yield and calcium content of oyster mushroom were explored.In order to provide reference for the production and related research of oyster mushroom.The results showed that 2%-4% hydrated lime in the substrate could significantly promote the mycelial growth of oyster mushroom,the highest yield and biological efficiency of P.pulmonarius were obtained from the substrate formula with 2% hydrated lime,which with yield and biological efficiency of 198.20 g·bag^-1 and 104.32%,the highest yield and biological efficiency of P.ostreatus and P.djamor were obtained from the substrate formula with 4% hydrated lime,their yield exhibited 180.60 g·bag^-1 and 241.87 g·bag^-1,and the biological efficiency were 95.05% and 127.30% respectively.The calcium content of fruit body obtained from different hydrated lime substrate was 0.13-0.30 g·kg^-1,but it did not show obvious trend with the increase of supplementary hydrated lime in substrate.In conclusion,it is suitable to add 2%-4% hydrated lime to the substrate of oyster mushroom,and the exact content depend on the species.The calcium content of oyster mushroom fruiting body did not affected by the level of hydrated lime in substrate.