The series of copper-doped strontium titanate materials with the assumed formula SrTi_1−xCu_xO₃ (where x = 0.01, 0.02, 0.05) were obtained by the sol–gel method. The synthesis of materials was undertaken towards evaluation of the possibility of their application in modern technologies in the field of energy storage and conversion. Materials were obtained in the form of powders and sintered bodies. Both types of these materials were tested for structural (XRD analysis), microstructural (SEM), reduction-oxidizing properties (TPR/TPOx methods). For sinters also electrical properties (conductivity and Seebeck coefficient) were determined. The phase composition analysis and the TPR results showed significant differences between the samples in the form of powders and sinters. The influence of copper oxide melting on the materials properties was observed. The measurements of the Seebeck coefficient confirm that copper is an acceptor dopant for strontium titanate. The results of total conductivity measurements carried out in the air atmosphere indicate that the addition of copper causes an increase in conductivity, with the highest value obtained for the material with the highest amount of copper introduced.