AbstractThe objective of this study is to investigate and evaluate the effectiveness of broadband radar cross‐section (RCS) reduction using a radar‐absorbing structure combined with geometric control of edges. The proposed novel design uses a radar‐absorbing structure combined with a serrated edge structure to efficiently improve the absorbing performance of the edge. The primary principle of the RCS reduction in the proposed novel structure is multiple scattering inside the corner reflector shape formed between the serrated edges. Although the absorbing performance of the designed planar absorber has narrowband absorption, the absorber combined with a serrated edge exhibits broadband RCS reduction. In designing a serrated edge shape, a foam core, which is a low‐density and lightweight material, is used to minimize the weight increase. The edge return becomes important for the low observable aircraft platform; hence, the proposed design can be a promising structure for further RCS reduction.