In recent years, with the wide application of hydrogels in flexible wearable electronic devices, the preparation method of hydrogels inspired by mussels has received more and more attention. However, on the basis of this method, how to prepare hydrogels with excellent mechanical properties, sensing properties, self-healing properties and swelling stability is still a challenge. In this paper, based on the chemical and physical interactions between polymer molecular chains, Fe³⁺/TA@CNF-PAA-VTES hydrogels were prepared by adding vinyl triethoxysilane ( VTES) into the precursor solution of hydrogels, using polyacrylic acid ( PAA ) and nanocellulose coated with tannic acids (TA@CNF) as raw material of hydrogels. The hydrogel was characterized and tested by scanning electron microscope, universal tester, rotary rheometer and digital source meter. The results show that the maximum tensile strength of Fe³⁺/TA@CNF-PAA-VTES hydrogel is 0.11 MPa, and it has excellent self-repairing performance. The sensitivity of Fe³⁺/TA @CNF-PAA-VTES hydrogel reaches 5.27 in the tensile strain range of 0% ~ 300% , which can be used to monitor the motion information of human body parts. More importantly, Fe³⁺/TA@CNF-PAA-VTES hydrogel shows better swelling stability in the pH range of 5~9, which can cope with complex use environments in daily life. Therefore, Fe³⁺/TA @CNF-PAA-VTES has a broad application prospect in the field of flexible wearable sensors.