The surface modification of silver coated silica microsphere (SiO₂/Ag) was carried out by using excellent bonding properties of polydopamine (PDA) to improve the mechanical properties of conductive silicone rubber without affecting the conductivity of conductive silicone rubber. The results show that PDA surface modification can improve the dispersion of SiO₂/Ag in silicone rubber. By controlling the reaction time, controllable thickness of PDA layer can be achieved so that controlling the conductive silicon rubber conductivity can be achieved. The Payne's effect, loss angle of tangent (tanδ), optimum curing time (T₉₀), contact angle and tensile strength of conductive silicone rubber filled with modified SiO₂/Ag reach the optimum state when the PDA coating time is 8 h and electrical performance meets application standards.