Recently V₂O₅, MoO₃, V-Mo-oxides are considered as a perspective cathode materials particularly for Li batteries. Mechanochemical activation (MChA) has been offered to prepare oxide materials in high-dispersed state that can be used for these aims. It is also known that MChA both individual V₂O₅, MoO₃ and their compositions was investigated in detail enough. However behavior of these activated oxides in aqueous media was not analyzed. Therefore studying of electrokinetic’s properties of above-mentioned oxides in aqueous solutions of electrolytes seems interesting and useful. It should be added that indicated characteristics both of initial and especially activated V-Mo-oxides are unknown in the literature. The said oxides were synthesized by MChA in air, water, ethanol and investigated using X-ray diffraction, DTA-TG, adsorption of nitrogen, FTIR, SEM. Use of the zeta potential studies of oxides by electrophoresis migration could help to understand some properties. Particle size distribution and electrophoresis study were carried out using a Zetasizer 300 (Malvern Instruments) apparatus based on photo correlation spectroscopy. The potential zeta of the system has been determined as a function of pH for H₂O, 0.01 and 0.001 mol/dm3 solutions of NaCl. The electrokinetic properties of MoO₃, V₂O₅, MoO₃/V₂O₅ activated in various media were interpreted using surface complexation model. The ionization and complexation constants have also been determined. The pHiep values of MoO₃ and V₂O₅ reported in literature were ranged from 1 to 3. Low value of the pHiep of these oxides is the result of strong acidic properties of surface groups which form negative charge on the surface even in the solutions of relatively high concentration of H+ ions or adsorption of anions that may be formed during dissolution of these oxides. Figure presents zeta potential as a function of pH and for pure V₂O₅, MoO₃ and mixed V₂O₅/MoO₃ samples that was milled in different fluids. The pHiep of samples depends on the basic – acid properties of surface hydroxyl groups (which is determined by atoms that surround the oxygen in surface hydroxyl group). The preparation of mixed vanadium-molybdenum oxides in air leads to the formation of sample that exhibit surface properties similar to molybdenum oxide, whereas milling in ethanol leads to sample that has properties similar to vanadium oxide surface. This means that the substrate ratio and method of sample preparation results on the subsurface region composition and it may differ from bulk composition of particle. The surface hydroxyl groups on such oxides have acidic character.