Ferroelectric glass–ceramics, with a basic composition (1−y)(Ba0.70Sr0.30)TiO3-y(B2O3x SiO2), were synthesized by sol–gel method. The major crystalline phase is the perovskite, which exhibited volume nucleation. The formation of the crystalline phase, particle size, morphology, kinetics, and mechanism of crystallization of the ferroelectric in the glass matrix have been studied using differential thermal analysis, X-ray diffraction, and scanning electron microscopy. The kinetic parameters characterizing the crystallization of the perovskite phase have been determined using an Arrhenius model. The effect of glass content on the dielectric properties and the influence of the glass composition on the crystallization have also been investigated and are reported.