Six samples of lead bismuth borate glasses of the composition 40B2O3 + (60-x) PbO2+x Bi2O3; 0 ≤ x ≤ 50 wt% have been fabricated by tradational melt-quenching process and coded as Bi0Pb60 – Bi50Pb10. The amorphous character of the samples was examined by XRD evaluations. FTIR measurements have been performed in the range of 4000-400 cm−1. The optical absorption spectra of the prepared glasses were investigated among 190–1100 nm of UV–Vis spectra wavelength. Optical energy gap ( E g a p o p t i c a l ), Urbach's energy (Eu), refractive index (n), the single-oscillator energy (Eo), the dispersion energy parameter (Ed), and dispersion refractive index (no) were evaluated. Results revealed that ( E g a p o p t i c a l ) and (Eo) decreased with increasing Bi2O3 content, while other parameters increased. In this study, MCNPX Monte Carlo code has been employed to study the radiation shielding efficiency of the fabricated glass specimens at several energies varying from 0.356 to 2.506 MeV. The mass attenuation coefficient values obtained by MCNPX were in well accordance with those obtained by WinXcom program. The results have clarified that the mass attenuation coefficients enhanced with the increase of the concentration of Bi2O3 from 0 to 50 wt%. Achieved results revealed that increase in the concentration of Bi2O3 can lead to a significant improvement in the gamma photons attenuation.