The bulk production of silver coated silica microsphere (SiO₂/PDA/Ag) was realized by dopamine-assisted functionalization and subsequent elelctroless plating. X-ray photoelectron spectroscopy (XPS), wide-angle X-ray diffraction (WAXD) and scanning electron microscope (SEM) results show that the silver layer on the surface of silica microsphere was homogenous, continuous and compact with stable silver contents. The surface of SiO₂/PDA/Ag microsphere was much rougher than the one imported from U.S. The roughness will facilitate the electron tunneling effect of particles. The SiO₂/PDA/Ag microsphere maintains its intactness and strongly adheres to ethyl vinyl silicone rubber after the blending with silicone rubber. The mechanical and electrical characterizations of conductive silicone rubber show that tensile strength is 2.54 MPa, elongation at rupture is 122.3%, volume resistivity before and after thermal aging is 3.9 and 9.0 mΩ·cm.