Direct contact of materials with blood components may trigger numerous processes which ultimately lead to hemolysis, clot formation and recruitment of inflammatory cells. In this study, the blood-surface interactions for two inert bioinspired ceramic scaffolds obtained from natural resources; biomorphic carbon and silicon carbides (bioSiC) from different origins have been studied. The response of the blood in contact with carbon is well known, however little has been identified on the influence of their 3D porous structure. Moreover, to our knowledge, there is no reference in the literature about the hemocompatibility of biomorphic silicon carbide as a porous scaffold. The experimental results showed the surface energy to be crucial to evaluate the hemocompatibility of a material however the surface topography and material porosity are also parameters to be considered. Surface roughness modifies clot formation whereas for protein adsorption total sample porosity seems to be the key parameter to be considered for hydrophilic materials (biomorphic silicon carbides), while the size of the pores determines the hemolytic response.