In water-ethanol systems, the limiting equivalent conductances of electrolytes were obtained using conductometric method. Using TATB method, the limiting equivalent ionic conductances of Li+, Na+, K+, Cl-, and Br- ions were also obtained. The effective radii of corresponding ions were determined using Nightingale method. From the volume of the solvation shell, the four solvation numbers were suggested. The reasonable solvation numbers (hH2O+hO) were estimated by comparing the values obtained by from the various suggested methods. The isosolvation point of ion in water-ethanol estimated was found to be larger than that of in water-methanol. This result agree with ET (solvent polarity) values of solvents. From the reasonable solvation numbers of ions in water-ethanol, the selective solvents of corresponding ions in water-ethanol were obtained.