An Eco‐Efficient and Sustainable Strategy for Fabricating High‐Strength Agricultural Fibers

High‐value utilization of renewable biomass resources is of great significance for achieving ecological and societal sustainability. It remains highly desirable to convert agricultural residues into high‐performance regenerated cellulose fibers in a green and scalable manner. However, the fabrication of superior agricultural regenerated fibers is demanding due to the inherent anti‐depolymerization structure and low degree of polymerization of agricultural cellulose. Here, we demonstrated a recyclable and eco‐efficient process enabling the selective extraction of cellulose from agricultural residues using a novel acid deep eutectic solvent system, and proposed a stretch‐induced alignment and spatial confinement strategy to realize scalable fabrication of high‐strength and high‐toughness regenerated fibers. The deep eutectic solvent presented efficient delignification and tailoring capacity for agricultural residue, yielding cellulose with a high purity of 91.2% and a crystallinity of 72.6%. The resultant fibers addressed the intrinsic limitations of agricultural cellulose through the formation of aligned nanofibril structures and densified hydrogen‐bonding networks, exhibiting a tensile strength of 852 MPa and a toughness of 110 MJ m −3 . This work establishes a foundational pathway for producing high‐performance bio‐based fibers derived from agricultural residues, advancing sustainable materials innovation and circular bioeconomy development.