Metamaterials are artificially engineered materials that reveal unconventional mechanical properties that are derived from repeated unit structure. Mechanical metamaterials have some distinctive features such as negative Poisson’s ratio or ultra-light weight with high stiffness. Here, we analyze energy absorption properties of soft urethane specimen composed of various kinds of structures by using finite element analysis. In order to improve the energy absorption properties, a modification of structure is suggested by reconstructing the equation of the structure. Also we conduct impact test with 3D printed specimens and analyze the energy absorption properties of various kinds of structures including bulk, P, PN, and the structure developed by research.