To provide a nonlead glass composition which has good acid resistance and is capable of retaining a softening temperature comparable to that of a lead-based glass used conventionally, and can solve problems of a conventionally used Bi2O3-based glass in the glass softening point and the acid resistance.

This nonlead glass composition comprises, in terms of an oxide, 55-75 wt.% Bi2O3, 5-15 wt.% B2O3, 4-12 wt.% SiO2, 3-12 wt.% ZnO, 3-10 wt.% Al2O3 and 0.1-5 wt.% ZrO2.