A new method of molecular structural characterization (MSC) called the molecular vertex distance index (MVDI) is constructed and used to describe the structures of benzene halides. Two quantitative structureproperty relationship (QSPR) models of octanol-water partition coefficients (lgKow) are obtained through multiple linear regression (MLR) and partial least squares regression (PLSR). The estimation stability and generalization ability of the models are analyzed by both internal and external validations. The results show that the models constructed in this work can provide satisfactory estimation stability and favorable predictive ability.