Abstract: This paper reports the measured conductance of KBr,KSCN,KClO₄ and KIin the mixed solvent of DMF with 1,4-dioxane at various ratios,the viscosity of the mixed solvent and the density of the salt solution.According to the conductance equations,namely,Pitts equation,Fuoss-1978 equation and Lee-Wheaton equation,the experi-.mental data were fitted on computer to get the limit molar conductance of salt at infinite dilution Ao, the ionic association constant Ka,and the distance parameter between cation and anion R.The suitability of the theoretical equations and the interaction of ion-ion-solvent molecule were discussed.