Abstract: Samples were prepared by four different processes, with the same formulation of TiO₂+ 0.3mol% （SrCO₃+ Bi₂O₃+ SiO₂）+ 0.075mol% Ta₂O₅. The influences of single sinter process and pre- sinter process on the electrical properties of TiO₂-based varistor ceramics were studied. It was measured with breakdown voltage, nonlinear exponent, complex impedance, I-V, barrier height, dielectric constant and dissipation. It is found that single sinter process makes breakdown voltage lower （E_10mA= 7.9V· mm^-1） and apparent dielectric constant bigger（ ε _ra=5.88× 10⁴）. And it is analyzed theoretically.