This paper demonstrates the superior capabilities of Ultra-High Frequency dielectrophoresis (UHF-DEP) to sort populations of biological cells based on their intracellular dielectric characteristics. The proposed concept combines both hydrofluidic and repulsive dielectrophoresis forces into a microfluidic lab-on-chip to create a UHF-DEP cytometer. The main objective is to sort different types of cells using only negative dielectrophoresis principle. The idea is to select proper frequency for the applied electric field in order to produce different intensity of repulsive DEP forces related to the cell type. This sorting principle, without positive DEP, limits strong interaction of cells with the electric field, which could induce their permanent trapping during cytometer operation and reduces the efficiency of the cell sorting. Results presented in this paper demonstrate the capability of an effective sorting for mesenchymal cells.