This study investigates the magnetocaloric effect of La0.7Sr0.3Mn0.95Ni0.05O3 manganite, with a primary focus on leveraging the mean-field theory as a powerful tool for analysis. By applying this theoretical framework, alongside the Law of Approach to Saturation (LAS), key parameters such as saturation magnetization (Mo), total angular momentum (J), gyromagnetic factor (g) , and exchange parameter (λ) were determined. The mean-field theory proved essential for simulating the isothermal magnetization M (H,T) and the magnetic entropy change -∆SM (T)curves, providing a comprehensive understanding of the material’s magnetocaloric behavior. Despite its simplifications, the mean-field approach serves as a crucial starting point for modeling complex magnetic systems and offers valuable insights into the material’s thermodynamic properties.