In this study, we report the structural, optical, and dielectric properties for La-doped BaSnO3 and ZnSnO3 solid solutions, La0.03(Ba1−xZnx)0.97SnO3 (x = 0,0.1,0.5,1) prepared at 1100 °C by isovalent substitution of Zn+2 at the Ba+2 site using the conventional solid-state reaction route. Structural data shows the transformation from cubic perovskite to orthorhombic perovskite structure as the amount of Zn increases in La-doped BSO samples. A minor pyrochlore phases, La2Sn2O7 and Ba2SnO4 were found in the XRD. This paper mainly focuses on understanding the contribution of physical phenomena of ac conductivity in terms of dielectric properties. The dielectric properties of the composites follow non-Debye type behavior. There was a moderate increase in the dielectric constant from 10.07 to 334 at 20 Hz, and 2.99–133 at 1 kHz, respectively, as we increased the amount of Zn, which is high as compared with other reported dielectric materials. By using Jonscher's power law, ac conductivity was found to increase in LZSO samples. This conduction mechanism due to the hopping of ions between coordination sites present in the composite and can be understood by the classically correlated barrier hopping phenomenon. Furthermore, the trivial loss of electromagnetic waves over a given frequency range demonstrates the great potential of La-doped ZnSnO3 materials to be utilized in ground penetrating radar systems, communication systems, and energy storage devices.