Abstract: Effect of co-doping V⁵⁺-Sr²⁺ on the properties of TiO₂ varistors ceramic was studied. V⁵⁺-Sr²⁺ co-doped TiO₂ samples were prepared by adopting the solid phase sintering method. XRD and SEM were carried out to measured the microstructure and chemical composition of V⁵⁺-Sr²⁺ co-doping TiO₂. Based on different sintering temperatures and V⁵⁺-Sr²⁺ co-doping content, electrical properties of V⁵⁺-Sr²⁺ were tested out by using the parameters instrument. The results show that secondary phase is observed in V⁵⁺-Sr²⁺ doped TiO₂ samples when the V₂O₅ doped amount is 0.35 mol%. With SrCO₃ doping content and sintering temperature increasing, varistor voltage and nonlinear coefficient of V⁵⁺-Sr²⁺ co-doped TiO₂ samples present different trends to change. 0.5 mol% Sr²⁺ doped samples sintered at 1 300℃ possess the optimal properties with a voltage of 16.3 V/mm and a nonlinear coefficient of 5.6.