A procedure in which Stokes diffusion cell was used is given for the determination of the Stokes diffusion constant for the binary liquid systems. Experiments were repeated until reproducible results were obtained. The effect of stirring on diffusion was examined and the stirring rate of 60 rpm was used in subsequent experiments.The diaphragm of the cell was calibrated at 298 K by diffusing 0.1 N potassium chloride. The experimental cell constant(?) was found 0.1997 cm-2. The binary experiments were performed in a temperature controller water bath at 290 K. The experimental diffusion coefficients of the dimethylphtalate-acetic acid, diethylphtalate-acetic acid and benzyl alcohol-acetic acid were found 0.927x10-5cm2/s, 0.623x10-5cm2/s and 1.067x10-5cm2/s, respectively. Furthermore, diffusion coefficients were calculated by the Scheibel and Wilke-Chang methods and compared with experimental values.