The Ca0.8Sr0.2TiO3 ceramics with different amounts of glass additions were successfully prepared by liquid phase sintering and used as dielectric barriers in a cylindrical dielectric barrier discharge reactor to decompose carbon dioxide at atmospheric pressure. It is found that the surface resistivity increases with increasing glass content. While the dielectric constant does not change obviously with the increase of the glass content in the investigated temperature range. The scanning electron microscope observations indicated that both the grain size and the thickness of intergranular glassy phases increase with the increase of the glass content. More importantly, the conversion rate and conversion efficiency of carbon dioxide improves with the increase of glass content in the ceramics. Furthermore, a combined discharge analysis and dielectric characterization are modeled with a Malter effect approach. From this model, it is possible to interpret the relationship between the conversion characteristics and the glass content in the ceramic samples.