Liquid gallium-yttrium alloys were studied by high-temperature calorimetry at 1750 K. Two calorimetric experiments were performed and the yttrium partial enthalpy of mixing (Delta(mix)(H) over bar (Y)) was measured up to the yttrium mole fraction of 0.6. The integral enthalpy of mixing (Delta(mix)H) was calculated by Darken's method. The concentration dependencies of the Delta(mix)(H) over bar (Y) and Delta(mix)H were represented via polynomial series. The experimental results were compared with literature data on Delta(mix)H, standard enthalpies of formation of yttrium gallides and yttrium partial enthalpy of mixing at infinite dilution. The agreement of the values obtained and those in the literature is satisfactory. (C) 2005 Published by Elsevier B.V.