Perovskite (Ba,Sr)TiO₃ glass ceramics were crystallized in the presence of La₂O₃ for glass ceramic system [(Ba_1-xSr_x)TiO₃]–[2SiO₂–B₂O₃]–[K₂O]–[La₂O₃] (x = 0.0 and 0.4). The formation of major crystalline phase of BaTiO₃ along with secondary phase of Ba₂TiSi₂O₈ was confirmed by X-ray diffraction (XRD) studies. Major crystalline phase was clearly seen in the micrographs of (Ba,Sr)TiO₃ borosilicate glass ceramic samples. The prepared glass ceramic samples showed very high values of toughness and elastic modulus. Barium strontium titanate (BST) glass ceramics are used in barrier layer capacitors for storage of high energy due to their very high dielectric constant and low dielectric loss.