The fish-shaped phase diagram of the ternary system (water + hexadecane + dipropylene glycol n-propyl ether) under atmospheric pressure was performed at constant water/hexadecane mass ratio (1/1). The upper critical solution temperature of the ternary system was determined as 314.00 K. Liquid + liquid equilibria of the system were measured at T = 298.15, 308.15, and 318.15 K under atmospheric pressure. The experimental data of liquid-liquid equilibria were further correlated with the NRTL model. (c) 2013 Elsevier B.V. All rights reserved.