Using oompnter simulation,we examined the influences of various experimental parameters on pore size distributions as determined by elution chromatography.The influences are different for two types of adsorption isotherms.The changes in saturated vapor pressure of nitrogen and total gas velocity have more profound effects on the pore size distribution.If the pore size only is to be obtained from experiments,then it was found that the shapes and leap regions of the adsorption isotherms are crucial,hence it is possible to reduce the number of observations on the other parts of the isotherm without reducing the accuracy of the determinations.