Strontium- and magnesium-doped lanthanum gallate (LSGM) has been considered as a promising electrolyte for solid oxide fuel cell (SOFC) systems in recent years. In this work synthesis, electrochemical properties, phase evolution, and microstructure of an all-perovskite electrolyte-supported SOFC based on (LSCM) porous anode, (LSGM-2030) electrolyte, and cathode at intermediate temperatures are studied. The phase evolution of synthesized LSGM and LSCM powders has been investigated, and it validates that there is no reaction between LSGM and LSCM at sintering temperature. The characterization study of the synthesized LSGM also indicates that sintering at gives higher electrical conductivity compared with the currently published results, while for the pellets sintered at and the conductivity would be slightly lower. The effects of the firing temperature on the bulk and grain boundary resistivities are also discussed.