Besides various materials, glass becomes very important, as it has started to be used in many applications. Thus, their radiation shielding properties should be determined for safely using in critical applications such as for medical purposes With this in mind, the present study investigated the radiation shielding parameters of waste soda-lime (SLS) containing varying amounts of lanthanum oxide (La2O3). The La2O3 content was added as 0.005, 0.05 and 0.5 in wt% into waste SLS glass, and four different glass specimens (La-0, La-0.005, La-0.05, and La-0.5) were produced via conventional melting technique. The linear attenuation coefficient for glass samples was measured in the photon energies of 511,835 and 1,275 keV and the results were compared with the calculation done by XCOM. One can conclude that adding lanthanum oxide to waste glass is an effective way to improve radiation shielding properties of glass. That is, the sample of La-0.5 could provide a higher linear attenuation coefficient while lower half-value thicknesses. Further, the findings obtained both in calculation and experimental showed a good agreement for all types of glass and also for all energies.