In this study, a series of 75TeO2-5Li2O-10ZnO-(10-x)Nb2O5-(x)Er2O3 (where x  = 0, 0.5, 1.0, 1.5, 2.0 and 2.8 mol%) glasses have been surveyed in terms of photon and neutron shielding characteristics. For this aim, 3 × 3 inch NaI(Tl) detector has been simulated in order to detect photons. Afterwards, the mass attenuation coefficients (μ/ρ) and some shielding quantities such as half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff), effective electron density (Nel), equivalent atomic number (Zeq) and exposure build-up factor (EBF) have been calculated. The obtained MCNPX results of all the glasses have been compared and approved with those of XCOM program. Also, their gamma ray buildup factors have been determined in a wide energy range of 0.02–20 MeV for penetration depths up to 15 mfp. Moreover, neutron attenuation abilities of glasses have been evaluated by estimating neutron total effective removal cross section. The results showed that Er2O3 partial replacement of Nb2O5 in 75TeO2-5Li2O-10ZnO-(10- x)Nb2O5-(x)Er2O3 glass system enhances photon and neutron attenuation characteristics. It can be deduced that obtained results from the present investigation can be useful to understanding of influence of Er2O3 on nuclear radiation shielding properties of tellurite glasses. Keywords: Radiation shielding, Er2O3, Tellurite glass, MCNPX code