Herein, an injectable multifunctional hydrogel based on dopamine grafted hyaluronic acid and phenylboric acid grafted methylcellulose was fabricated for promoting the repair of diabetic wounds. The prepared hydrogel possessed multifunctional properties including rapid gelation time (less than 10 s), self-healing, high water absorbency, tissue adhesiveness and excellent antioxidant activity. After loading Ag nanoparticles and the recombinant humanized collagen type III with high affinity to cells, the hydrogel exhibited properties of pH-/H₂O₂-responsive drug release profile, promoting cell proliferation and ideal antibacterial activity. Moreover, the in vivo experimental results demonstrated the prepared hydrogel could significantly accelerate wound repair by enhancing the collagen deposition and granulation tissue regeneration, reducing the expression of CD68 and improving the production of Ki67 and CD31 simultaneously. In conclusion, these multifunctional injectable hydrogels possessed great potential in chronic wound dressings.