Current work presents the synthesis of B2O3–Gd2O3–Li2O–Na2O–LiF‒Sm2O3 glass system via melt-quench approach and scrutiny of its mechanical, thermal, structural, physical, and nuclear radiation attenuation aspects. Raman scattering and Fourier transform infrared spectra revealed B–O stretching modes of BO4 groups linked to BO3 units with nonbridging oxygen atoms and BO3 and BO4 units' existence in the glass structure. By differential scanning calorimetry, glass transition and crystallization temperatures are identified. Relevant analysis showed all glasses' good thermal stability where glass transition temperature varied at 372–407 °C range. ΣR (fast neutron removal cross-section) and for energy 0.025 eV neutrons σT (total cross-section) are computed. In all glasses, 49.25 B2O3–10Gd2O3–10Li2O–10Na2O–20LiF-0.75Sm2O3 (mol%) sample holds higher ΣR (= 0.10207 cm−1). 48B2O3–10Gd2O3–10Li2O–10Na2O–20LiF–2Sm2O3 (mol%) glass possesses greater σT (= 736.675 cm−1) for thermal neutrons, hinting at added Sm2O3's favorable influence as Sm owns a better ability for neutron absorption than B. By Phy-X/PSD, μ/ρ (mass attenuation coefficient) is obtained at photon energy extent 15 keV‒15 MeV. Sm2O3 inclusion from 0 to 2 mol% minorly enhanced the μ/ρ values. Buildup factors estimated via geometric progression fitting method at 1–40 mean free path and energy 0.015–15 MeV span are maximal at medium energy region owing to Compton scattering process. 48B2O3–10Gd2O3–10Li2O–10Na2O–20LiF–2Sm2O3 (mol%) sample shows superior γ-ray blocking capacity in all glasses, suggesting Sm2O3's positive effect. Elastic moduli and Poisson's ratio are computed theoretically by bond compression and Makishima–Mackenzie models. It is identified that all glasses could tolerate longitudinal stress over shear stress.