<p>The rapid accumulation of electronic waste due to high consumption of electronics is a growing global concern. The development of sustainable electronics with both recyclability and desired properties is urgent to tackle this problem. However, existing open-loop recycling and closed-loop chemical recycling approaches suffer from either compromised performance of recycled materials or harsh recycling conditions. Here we develop a closed-loop bio-recyclable cellulose-based dielectric film for sustainable electronics. We combine a biomanufacturing strategy—aerosol-assisted biosynthesis—with specific enzymatic degradation to obtain closed-loop biological recyclability. The spontaneous behaviours of bacteria in aerosol-assisted biosynthesis and the artificial sandwich structural design synergistically impart the dielectric film with high tensile strength, a low dielectric constant and a low thermal expansion coefficient, enhancing its applicability. This work offers a viable approach to improve the circularity of electronics, paving the way to a more sustainable electronics industry.</p>