The study of microwave-absorbing materials and microwave-absorbing structures holds significant importance in fields such as human health and military defense. With the advancement of information technology, the severity of electromagnetic pollution has increased, resulting in a greater need for microwave protection. Simultaneously, additive manufacturing has garnered significant attention from scholars due to its ability to utilize diverse materials and construct complex models with flexibility. In this paper, we have successfully achieved the integration of design, manufacturing and evaluation. Specifically, we have combined material extrusion technology with microwave-absorbing materials and structures to conduct research on absorbing functional composites using material extrusion. By employing large variation genetic algorithm, we designed an electric-loss honeycomb metastructure (ELHM). The ELHM demonstrates effective broadband absorption performance within the frequency ranges of 2–6.8 GHz and 10.4–40 GHz. It maintains excellent absorption properties even during oblique incidence reflection tests under different polarization modes. Additionally, it exhibits outstanding load-bearing capacity.