The work aims to review the theories, practices and simplified methods for obtaining the buffering curve traditionally, and conduct an error comparison analysis with the buffering curves predicted and obtained through the two methods of energy density and stress energy, so as to obtain the buffering curve of expanded polystyrene (EPS) by the most convenient method. According to the requirements of the dynamic compression test method for packaging buffering materials in "Packaging Buffering Materials:Test Items, Dynamic Compression Test and Static Compression Test" (GB/T 8167-2008), EPS samples with densities of 20 and 25 kg/m³, drop heights of 250, 350, 460 and 760 mm, and material thicknesses of 25, 30, 35 and 65 mm were used. At least five data points on the curve were measured through experiments and the complete curve was drawn. Based on the principle of energy conservation, the stress energy-static stress curve, energy density-static stress curve and other corresponding buffering curves under this buffering material were calculated and drawn respectively. On this basis, the relationship formulas between the static stress, dynamic stress and unit volume absorbed energy of the buffering material were established to predict the maximum impact acceleration of the buffering material, thereby obtaining a method for fast obtaining of buffering curves. The buffering curves of EPS under different combination conditions were predicted and compared with the buffering curves obtained through experiments. The results showed that the predicted buffering curves under different combinations of drop height and material thickness were in good agreement with the experimental buffering curves. In conclusion, both of these two derivation methods can quickly obtain the buffering curve, significantly reducing the number of experiments, and also providing more possibilities for quickly obtaining the buffering curve.