This study focuses on the fabrication and acoustic absorption performance analysis of graded steel foam compared to uniform pore sizes. Using the pressureless powder space holder method, graded steel foams are successfully produced and subjected to acoustic absorption testing. This study examines the impact of porosity levels (52, 63%) and pore sizes (1.15, 4.4 mm) on acoustic properties and explores their linear relationship. Results indicate that the acoustic absorption performance of graded pore-size steel foam surpasses that of uniform pore-size steel foam in the frequency range of 100–6300 Hz. Specifically, samples with increasing pore sizes in the direction of the incident wave provide the best performance, with a maximum absorption coefficient of 0.71 at 6300 Hz. Meanwhile, uniform pore-size steel foam shows lower absorption coefficients, peaking at 0.58. Overall, optimal acoustic absorption is observed in positive gradient (from small to large pore sizes) samples with a porosity of 63%. This positive gradient configuration enhances the interaction between sound waves and the material, leading to superior absorption performance.