Abstract: The vapor pressure and the liquid-liquid equilibrium data for the partially miscible region of the aeetone-isobuWraldehyde-water ternary have been reported. The prediction for the vapor-liquid-liquid equilibrium in the partially miscible region of the ternary is fairly satisfactory with the use of the binary parameters of the three binaries reported in the Part I of this paper. In order to make the prediction better, maximum likelihood method was adopted. The binary parameters of the three binaries are estimated again by fitting the vapor liquid equilibrium data of acetone-water and acetone-isobuty-raldehyde, binaries as well as some of the ternary liquid-liquid equilibrium data.With these parameters, the prediction of the ternary liquid-liquid equilibrium is improved appreeiablly, while the prediction of the equilibrium of the corresponding binaries and the ternary in the mutually miscible region is still acceptable.