Selection of methods and relevant parameters is crucial for estimation of tight gas resources.The volumetric method was selected in this paper based on analysis of the advantages and disadvantages of different evaluation methods and relevant two key parameters were defined

namely tightness limit and gas saturation.The results show that volumetric method is the most reliable method to evaluate tight gas resource potential.However

the accurate determination of relevant parameters should be based on the features of tight sandstone reservoir.Tight sandstone reservoirs are generally cha-racterized by small throat

strong hydrophilicity and high bound water saturation.The size of throat controls the permeabi-lity.Hydrophilicity is controlled by clay mineral components and their contents rather than the total amount of clay mine-rals.The higher content of Illite is

the smaller the wetting angle is and the stronger the hydrophilicity is.The contrary is true for chloride.The balance relationship between gas buoyancy and capillary force determines the limits of reservoir properties

which is significantly influenced by wetting angle.The critical tightening limit progressively decreases from central to edge of the basin.Electric double layer formed by the strong adsorption water on Illite surface has strong conductivivity

which makes the Archie formula not suitable for the interpretation of tight gas saturation.While Indonesia's formula fully takes the influence of shale content into consideration

thus is more suitable for determining gas saturation of tight sandstone reservoir.