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Glasses with the compositions Pb2(1−x)Ti2xGe5O12+2x (x = 0.5, 0.4, 0.3, 0.2, 0) were prepared in order to study their electrical and optical properties. The density decreases with increasing Ti content in the glasses, and the refractive index exhibits a maximum at x = 0.4. The Raman spectra show that Ge is tetrahedrally coordinated in glasses. At a given temperature, the electrical conductivity increases with increasing Ti content while the dielectric constant shows a mixing effect that exhibits a maximum at x = 0.2. The temperature dependence of dielectric constant was discussed by means of the Langevin theory.