A glass composition that is lead-free, and that, when used in a PDP, suppresses coloration of a dielectric layer, a transparent conductive film and a glass substrate, and suppresses reduction in transmittance of the dielectric layer. The glass composition is includes GeO2 0.1-20 wt %, B2O3 3-35 wt %, ZnO 4-45 wt %, Bi2O3 10-80 wt %, is free of PbO, and SiO2 content is not more than 0.5 wt %. It is preferable to further include in the glass composition Al2O3 up to 8 wt % and at least one selected from the group consisting of MgO, CaO, SrO, and BaO, up to 20 wt %.