The development of continuously degradable and recyclable polymeric composites with superb mechanical properties, which can extend the service life of materials and reduce the environmental impact, will make a significant contribution to global sustainability. In this study, poly(vinyl alcohol) (PVA)-based composites (D-PVA-Fe-TA) with degradability, recyclability and excellent mechanical properties are prepared by complexation of 3,4-dihydroxybenzaldehyde-grafted PVA (D-PVA), tannin (TA) and Fe3+ ions in dimethyl sulfoxide (DMSO), and then dialysis in deionized water and glycerol (Gly). The two-step dialysis process, playing a crucial role in reducing the free water of D-PVA-Fe-TA composites, enhances the formation of reversible of hydrogen-bonding and the reinforcement of self-assembled Fe3+-chelation between TA and D-PVA, and facilitates the fabrication of PVA-based composites with a breaking strength of ≈ 18.7 MPa, an elongation at break of ∼ 812 % and a toughness of ≈ 86.81 MJ/m3; Meanwhile, the resulting homogeneous and dense structure of D-PVA-Fe-TA composites hinders the penetration of Gly solution, thereby enhancing the bonding strength and environmental adaptability of D-PVA-TA-Fe composites within the temperature range of −20℃ to 60℃. Furthermore, the as-prepared D-PVA-TA-Fe composites exhibit recyclability for multiple cycles. When placed under soil culture medium, the resulting composites can be degraded without the need for manual interference. This study presents a novel strategy for the fabrication of materials possessing excellent mechanical strength, environmental adaptability, recyclability and degradation, which have great potential for taking the place of conversional composites in specific conditions.