Lightweight electromagnetic absorbers made of polymers and multiwall carbon nanotubes (MWCNTs) have attracted a lot of attention because of their potential to shield next-generation electronics devices from electromagnetic radiation without reflecting it back into space. In this research, a flexible foam composed of MWCNTs and polyvinylidene fluoride (PVDF) is developed. This foam is designed to be an electromagnetic shielding material that is both flexible and absorption-dominant, reducing electromagnetic interference. The solvent approach is used to fabricate the PVDF-MWCNT foam. It is discovered that the foam has a porosity of 88.9%. Each cell in the PVDF-MWCNT foam is formed in a porous layered manner. The foam demonstrates a dielectric constant (ϵ′) of around 7.19 and dielectric loss (ϵ " ) of 4.46 at 9.96 GHz as calculated from MATLAB using the Nicolson− Ross−Wire algorithm. This developed EM absorber exhibits a high shielding efficiency of 78.46 dB. With an ideal reflection loss of −26.5 dB, this absorber attains the desired outcomes. The electromagnetic shielding performance is supported by calculations of the impedance matching degree, which was found to be 0.54. The PVDF-MWCNT foam displayed absorption-dominant characteristics, with a significantly low shielding due to reflection. This newly developed foam EM absorber has proven itself capable in a variety of commercial and stealth-related applications.