The fabrication process of PbO–Bi₂O₃–ZnO–B₂O₃(PBZB) glasses involved the application of a melt quenching technique. The glass samples were revealed through X-ray diffraction (XRD) analysis to be amorphous in nature. Fourier-transform infrared (FTIR) spectra, ranging from 4000 to 400 cm⁻¹, exhibited peaks and bands indicating bending and stretching vibrations associated with the constituent groups in the glasses. The Raman spectra indicated that non-bridging oxygens (NBOs) formed with PbO’s incorporation into the network. To investigate the UV–Vis spectra of the glass, the Derivation of Absorption Spectrum Fitting (DASF) method was employed. This analysis predicted a decrease in energy band gap values, which was attributed to the increased presence of NBOs within the glass network. The prepared glasses’ radiation-shielding properties were reported using Phy-X software in the range of 0.284–1.333 MeV, where it was found that the mass attenuation coefficient (MAC) follows the order of PBZB1 < PBZB2 < PBZB3 < PBZB4, which means a positive correlation of the samples’ MAC with the glasses’ PbO content, or an inverse correlation with the glasses’ B₂O₃ content. Thus, the sample characterized by the highest content of PbO, or the least B₂O₃ content, has the greatest radiation shielding ability. The ratio between the tenth value layer for the PBZB1 and PBZB4 samples was estimated, with the results demonstrating the ratio to be higher than one, thus indicating that PBZB1’s TVL is always greater than PBZB4’s TVL. From the ratio between the TVL, we found that the addition of PbO causes a reduction in the thickness of the glass that is needed to attenuate the incoming photons. The PBZB4 sample (which contains 70 mol% of PbO) has the greatest advantage over the other materials in the glass system at lower and higher energies, while having a slightly reduced advantage at medium energies. PBZB4 possesses the lowest HVL value, thus qualify as the best shielding material.