A hybrid approach of CALPHAD and first-principles calculations was employed to perform a thermodynamic modeling of the Sn-Sr system. The experimental phase diagram and thermodynamic data available in the literature were critically reviewed. The enthalpies of formation for the 6 stoichiometric compounds (i.e. Sr2Sn, Sr5Sn3, SrSn, Sr3Sn5, SrSn3 and SrSn4) at 0K were computed by means of first-principles calculations. These data were used as the experimental values in the optimization module PARROT in the subsequent CALPHAD assessment to provide thermodynamic parameters with sound physical meaning. A set of self-consistent thermodynamic parameters was finally obtained by considering reliable literature data and the first-principles computed results. Comprehensive comparisons between the calculated and measured quantities indicate that all the reliable experimental information can be satisfactorily accounted for by the present thermodynamic description. (C) 2011 Elsevier B.V. All rights reserved.