Measurements of the change of the pour point depression (DeltaT(PP)) were performed for the wax solutions made of four solvent mixtures: ethyl acetate/hexane (EA/HEX), 1,2-dichloroethane/cyclohexane (DCE/CYH), butanone/heptane (MEK/HEP), and acetone/chloroform (AC/CF) doped with EVA polymers. The values of DeltaT(PP) increase significantly with increasing of the selective solvent EA, DCE, MEK, and AC components, for the vinyl acetate (VA) segment in EVA copolymers, in the solvent mixtures. The solvent effect of DeltaT(PP) occurring in wax solutions can also come from the solutions of EVA polymer, which were prepared by solvent mixtures with various compositions and used as parent solutions of EVA pour point depressant. From the experimental results such as the NMR of EVA macromolecules; viscosities of EVA, waxes, and their blends; and solubilities of wax with and without EVA macromolecules in the solvent mixtures, the complexation between wax molecules and ordered ethylene segment, and wax solubilization within ordered ethylene segments in EVA macromolecules are suggested for qualitative description of the observed significant variation of DeltaT(PP).