提出1种水的分子热力学模型,从微扰理论出发,建立了自由能及其它热力学函数的关系式.水分子间作用包括硬球、色散、静电及诱导几个部分.通过同时关联0～300°C下饱和水蒸气压及液体密度数据获得分子参数,还预测了水的蒸发焓及饱和水蒸气的比容,比较了文献中处理水的几种理论方法.结果表明,本模型简单,且较接近实际. Based on the perturbation theory, a relational formula between free energy and other thermodynamic functions is established. The interaction between water molecules includes hard spheres, dispersions, static electricity and inducing several parts. By simultaneously associating 0 ~ 300 ° C, the molecular weight of saturated water vapor pressure and liquid density were obtained, the enthalpy of evaporation and the specific volume of saturated water vapor were also predicted, and several theoretical methods of treating water in the literature were compared. The results show that this model is simple, Close to reality.