In this paper, four samples of bismuth barium telluroborate glasses in the chemical composition of 20Bi(2)O(3) + 30BaO + xEr(2)O(3) + (30 - x)B2O3 + 20TeO(2), here x is between 0.05 and 2 mol%) coded as BTBE1, BTBE2, BTBE3, and BTBE4 are reported for potential use in nuclear shielding applications. Geant4 simulations were well designed to obtain the mass attenuation coefficient, mu/rho for the BTBE1 - BTBE4 specimens at 356 keV-2.51 MeV photon energies. Then, the obtained results are confirmed by using WinXCOM platform. The mu/rho values were used to assess the nuclear shielding capacity of BTBE1 - BTBE4 specimens in terms of effective atomic number, Z(eff), mean free path, MFP, and half-value layer, HVL. Additionally, the buildup factors of BTBE1 - BTBE4 specimens were computed via G-P fitting method at 0.015-15 MeV photon energies and up to 40 mfp (penetration depths). Also, the neutron shielding capacity of the glasses was assessed by calculating the removal cross sections (Sigma(R)). Our results indicate that there is a remarkable enhancement in the gamma shielding features by adding Er2O3 content in the BTBE1 - BTBE4 specimens. It is found that BTBE4 and BTBE3 glass specimens have high shielding quality against nuclear radiation. Gamma-rays and fast neutrons shielding parameters of the BTBE1 - BTBE4 specimens are compared with several commercial and traditional shielding materials. These comparisons concluded that the reported glasses are quite useful for radiation protection purposes.