The dielectric behavior and electrical conduction in Bi doped SrTiO3 annealed in both oxidizing (air and oxygen) and reducing atmospheres (nitrogen and “hydrogen+argon”) are studied in this letter. The dielectric constant and electrical conductivity are greatly enhanced in the sample annealed in a reducing atmosphere compared with that annealed in an oxidizing atmosphere. A Mott’s variable range hopping (VRH) conduction mechanism, σ=σ0 exp[-(T0/T)1/4], is observed in a strongly reduced sample, where a significant dielectric relaxation process is present. No direct correlation is found between the VRH conduction and the dielectric relaxation. The underlying physics of these results are briefly discussed.