Abstract: The effects of some experiment parameters, such as powder size, sintering temperature, soaking time, the type of dopant and their content on electrical properties of TiO₂ varistor ceramics are summarized, as well as their crystal microstructures. The electrical properties include varistor voltage, nonlinear coefficient, dielectric loss, dielectric constant and so on. It is pointed that the research focus is on the development tendency in miniaturization and multi-functionalization of TiO₂ varistor ceramics.