Abstract: The purpose of this study is to evaluate the influence of the amount of coupling agent -MPS on the filler loading and mechanical properties of nano-ZrO2-SiO2 based dental resin composites. The nano-sized ZrO2-SiO2 composite powders were synthesized using colloidal silica and zirconium acetate under acid condition that were silanized using methacrylate functionalized silane (-MPS), and the dental composite material was generated by adding them to bisphenol A-biglycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) which were resin substrates. Fourier transform infrared (FTIR)、transmission electron microscopy (TEM)、thermogravimetric analysis (TGA) and laser particle analyzer (LPA) were adopted to characterize and analyze the ZrO2-SiO2 nano-particles before and after modification and the dispersion in organic resin substrates. It is found that inorganic particles were successfully modified using silane coupling agent -MPS which organic functional groups chemically bonded on the surface of ZrO2-SiO2. The surface modification reduces the particles aggregation and improves the dispersion in organic resin. The modified ZrO2-SiO2 and organic resin processing dental composite resin has been prepared with better-mechanical property. Significance. The silane used for the silanization of nano-ZrO2-SiO2 has a significant influence on the compatibility with resin substrates, filler loading and mechanical properties of the resin composite.