A study was conducted to demonstrate the effect of mechanical behavior of metallic hollow sphere foam. The study focused on demonstrating the effect of the architecture for a given constitutive material. The main objective of the study was, to analyze experimentally and numerically the plastic behavior of random packing of hollow spheres and determine the deformation mechanisms of the foams, as the function of geometrical features, such as spheres diameter, thickness, and neck size. A phenomenological model was also developed in a second step, to consider the deformation mechanisms and predict the proposed macroscopic mechanical behavior. Samples of 314 stainless steel hollow spheres were produced and characterized by X-ray microtomography and mechanically tested by in-situ compression test, to investigate the relationships between structure and mechanical behavior.