In this study, a complex oxide solid solution consisting of lanthanum gallate with partial substitutions for strontium and magnesium (La0.9Sr0.1Ga0.8Mg0.2O2.85) was synthesized by the sol???gel route, aiming to obtain a sinter active powder and a final material that could be stoichiometrically controlled. The thermal behavior of the synthesized powder involves several steps of decomposition. The linear shrinkage of green compacts up to 1500 ??C was 31%. The bulk conductivity of sintered specimens increases with sintering temperature up to 1400 ??C. The stoichiometry was maintained for sintering temperatures up to 1450 ??C. Elemental mapping obtained by energy-dispersive spectroscopy evidenced magnesium segregation at the grain boundaries. The overall results evidence the suitability of the synthesis method for preparing doped lanthanum gallate.Funda????o de Amparo ?? Pesquisa do Estado de S??o Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cient??fico e Tecnol??gico (CNPq)Coordena????o de Aperfei??oamento de Pessoal de N??vel Superior (CAPES)FAPESP: 13/07296-2CNPq: 305889/2018-4CAPES: 001