Liquid-liquid equilibrium (LLE) tie-line data for 2-methyl-1-propanol + 2-propanol + water were determined experimentally under atmospheric pressure over the temperature range of (298.15-348.15)K, respectively. A type 1 LLE phase diagram for the ternary system studied was got and the influence of temperature on the phase diagrams was reported, too. The Othmer-Tobias and Bachman correlations were applied to check the accuracy of the LLE data reported. Moreover, the experimental data got were regressed with the NRTL (alpha=0.2) and UNIQUAC activity coefficient models, meanwhile, the binary interaction parameters between each pair of components in the studied system were obtained. The root-mean-square deviation (RMSD) between the measured and calculated data was less than 0.0031 The results can be used to design and optimize the separation process of aqueous solution containing 2-propanol and 2-methyl-1-propanol. (C) 2012 Elsevier B.V. All rights reserved.