The rapid development of efficient high-temperature electrochemical devices stimulates the search for new electrolytic materials with high conductivity and excellent chemical stability. From this point of view, lanthanum-containing perovskites can be considered as suitable materials for solid oxide fuel cell applications. In this work, the successfully synthesis and comprehensive study of acceptor-doped lanthanum ytterbates, La1–xMxYbO3–δ (M = Ca, Sr, Ba; x = 0, 0.05, 0.1) is described. X-ray diffraction analysis showed all samples to possess an orthorhombic structure with the space group Pna21, whose stability was confirmed at temperatures up to 1000 °C. The high chemical stability of the materials with respect to carbon dioxide and water vapor was confirmed by SEM and XRD methods. The dilatometry data allowed the determination of thermal expansion coefficient values of ceramic samples, which are close to those for conventionally used YSZ electrolytes. The transport properties of the ceramic were studied in a wide range of temperatures (300–900°C) and oxygen partial pressures. It was found that ytterbates doped with 5 and 10 wt.% of strontium and 5 wt.% of barium exhibited the high electrical conductivity among other considered materials. Thus, these materials can be considered as promising proton-conducting electrolytes for various electrochemical devices.