Phosphate glasses are characterized by properties distinguished by comparison with those of others such as borates, silicates, and tellurides that can be used in many fields such as optics, electronics, medicine, environmental protection, etc. On the other hand, these pure phosphate glasses have low chemical durability, which limits their application. The addition of strontium to the glass considerably improves its durability. Using classical molecular dynamics simulations, this work investigated the influence of SrO addition on a glass phosphate structure with a nominal chemical composition of (100- x) P2O5 – x SrO (where x = 0, 5, 10, 15, ... 45 mol %). According to the progressive increase in the SrO content, the density of the simulated glass increased from 2.400 g/cm3 to 2.937 g/cm3, while its molar volume values reduced from 59.143 to 42.449 cm3/mol. The simulated glasses' short-range structure is described, and it agrees well with prior experimental and theoretical research. The increased SrO level in the glass resulted in the depolymerization of the phosphate network, according to simulations. Furthermore, we evaluated the aggregation parameters of the Sr-Sr pair, and it was most intense for the low SrO content, which can lead to the inhomogeneity of the phosphate glass network.