As the radiation shielding is important for human health, alternative materials are under research for using this purposes. Thus in this study, Magnesium Borosilicate Glasses were inspected for their radiation defensive mechanism. The glass compositions are 40MgO–30SiO2 – (30-x)B2O3–xLa2O3, where x = 0,2.5,5,7.5 (mol%). Lanthanum (III) oxide, known as lanthana, is an inorganic compound and in it contains the rare earth element lanthanum and oxygen. It can be used as a component of optical materials such as glass as it was used in this study. The variation of the linear attenuation coefficient (LAC) and some other parameters such as half value length (HVL), mean free path (mfp), effective atomic number (Zeff) and Effective electron density (Neff) with the amount of La2O3 (0, 2.5, 5, 7.5 mol%) in glass samples was studied. The Phy-X/PSD program was utilized for this purpose. The results demonstrate that LaO-7.5 (with composition of 40MgO–30SiO2 – 22.5B2O3–7.5La2O3) has the highest LAC value out of the prepared glasses, while LaO-0 has the lowest.