Yttrium-doped strontium titanate with B-site deficiency (Y 0.08 Sr 0.92 Ti 1−x O 3−δ ) is synthesized via conventional solid-state reaction. The effect of B-site deficiency on the lattice parameter, sinterability, microstructure and electrical properties of Y 0.08 Sr 0.92 TiO 3−δ is investigated. The charge compensation mechanism for B-site deficiency is proposed. The limit of B-site deficiency in Y 0.08 Sr 0.92 Ti 1−x O 3−δ is below 5mol % in Ar with 5% H 2 at 1500°C. The sinterability of Y 0.08 Sr 0.92 Ti 1−x O 3−δ decreases slightly with increasing deficiency level (x). Compared with Y 0.08 Sr 0.92 TiO 3−δ , the electrical conductivity of Y 0.08 Sr 0.92 Ti 1−x O 3−δ samples decreases while the ionic conductivity increases with increasing B-site deficient amount. It is assumed that the deficiency of Ti in Y 0.08 Sr 0.92 Ti 1−x O 3−δ is charge compensated by the increase of oxygen vacancy concentration and the decrease of Ti 3+ concentration. Y 0.08 Sr 0.92 Ti 1−x O 3−δ shows a relatively stable electrical conductivity at different oxygen partial pressures and displays an excellent chemical compatibility with YSZ electrolyte below 1200°C.