Abstract: Experiment were conducted by random design of two factors on 1-year Pinus massoniana seedlings inoculated by Suillus luteus SL7 & SL1, Cantharellus cibarius, Pisolithus tinctorius Strain Pt 715, Cenococcum geophilum Strain Cg SIV with different soil relative water content (65±5)%, (50±5)%, (35±5)% and (25±5)%.The result showed that ectomycorrhizal fungi could increase relative ans bound water content of leaves, reduce seedling RWC, free water and water saturation deficit to improve seedling moisture to strengthen the drought resistance of seedlings. Ectomycorrhizal seedlings had higher chlorophyll content and photosynthetic rate by promoting the absorption of nutrients with significant difference between different treatments.The photosynthetic rate, stomatal conductance, intercellular CO2 concentration and efficiency of resources use was improved by higher chlorophyll content of ectomycorrhizal seedlings by reducing the transpiration rate, stomatal limitation and photosynthetic oxygen consumption, stomatal resistance of moisture, and increasing water content.Drought resistant of ecotmycorrhizal seedlings was followed by S1>T>S7>G>C>CK.