The (Sr1−1.5xBix)TiO3 (0.0133⩽x⩽0.133) ceramic system reveals several sets of dielectric permittivity peaks in different temperature ranges. Dielectric permittivity and dielectric loss peaks were detected in the temperature range 500–800 K and in the present article the dielectric polarization behavior is presented and discussed. The activation energy of the dielectric relaxation is in the range of 0.99–1.12 eV. It is suggested that the permittivity peaks are related to the movement of oxygen ions or oxygen vacancies.