In this study we are interested in the modeling of the adsorption phenomenon of dye N719 on titanium oxide. Three adsorption isotherms of dye at three different temperatures: (293.15 K, 313.15 K and 333.15 K) are fitted by using a statistical physics treatment based on the grand canonical ensemble to deduce the adequate model in order to describe the adsorption process. The physio chemical parameters involved in the adsorption process have been deduced directly from experimental adsorption isotherms by numerical simulation. We will introduce six main parameters to describe the adsorption process, namely; two densities of dye receptor sites N-m1 and N-m2, the numbers of absorbed molecules per site n(1) and n(2), the concentrations at half saturation C-1 and C-2. In order to investigate the type of interaction between the dye molecule and titanium dioxide, we calculate the adsorption energies of the dye molecule using our statistical physics model and the known Dubinin-Radushkevich model for comparison. The numerical values of adsorption process energy (E-a) indicated a chemical adsorption allowing a strong bound to avoid a dye desorption which is very useful to keep a DSSCs in good working order. We apply then our model to deduce thermodynamic functions which govern the adsorption mechanism such as internal energy, entropy and free enthalpy. (C) 2016 Elsevier Ltd. All rights reserved.