The specific heat capacities of triethylene glycol monopentyl ether aqueous solutions have been measured from 278.15 to 338.15 K, over the wide concentration range by DSC. The apparent and partial molar heat capacities were calculated and the two-point scaling theory was used to analyze these data. Obtained results were discussed in terms of aggregation taking place in the solution and influence of the temperature on this process. The separation line between single-phase solution and two-phase system was determined using scanning calorimetry. (C) 2016 Elsevier B.V. All rights reserved.