The SiO₂-BaO-based glass-ceramics have become the focus of research in the field of high sealing resistance due to their high expansion coefficient and excellent high resistance, but the effect of rare earth oxide on modification of this kind of sealing glass-ceramics is rarely reported. Here, the effects of rare earth elements with different cation field strength (CFS) replacing traditional alkaline-earth oxide BaO on the network structure, crystallization properties, microstructures, and high-temperature resistivity of a new type of rare-earth rich-SiO₂-BaO-Ln₂O₃ (SBLn, Ln=La, Sm, Er, Yb) series glass were studied. With the increase of rare earth cation field from 2.82 in La³⁺ to 3.98 in Yb³⁺, the glass transition temperature (T_g), crystallization initiation temperature (T_x) and crystallization peak temperature (T_p) of SBLn glass are increased, implying that the SBLn glass with higher rare earth cation field strength is more stable. Crystalline phases of the four SBLn glasses are composed of BaSiO₃ and BaSi₂O₅ phases. When rare-earth cation field strength increases, the BaSiO₃ phase decreases while the BaSi₂O₅ phase increases. Rare-earth elements only exist in the glass phase and do not participate the crystal phase precipitation. The crystallization amount decreases with the increase of rare earth cation field, coefficient of thermal expansion (CTE) of SBLn glass-ceramic increases from 12.52×10^-6 /℃ to 13.13×10^-6 /℃ (30-800 ℃), but softening temperature decreases from 1313.5 ℃ to 1174.1 ℃. In short, the CTE, softening temperature and DC resistivity at 700 ℃ of the SiO₂-BaO-Ln₂O₃ glass-ceramics are greater than 12×10^-6/℃, 1150 ℃ and 10⁶ Ω·cm, respectively, indicating that the rare-earth-rich glass-ceramic sealant has a promising application prospect in the field of high sealing resistance, such as solid oxide fuel cell, oxygen sensors, platinum thin-film thermistor under elevated temperature.