Periodontal disease is a multifactorial, bacterially induced inflammatory disorder characterized by progressive destruction of periodontal tissues. Additionally, diabetes mellitus exacerbates periodontitis, resulting in expedited resorption of periodontal bone. However, methods such as mechanical debridement, anti‐inflammatory medications, and surgical approaches often fail to eradicate local infections and inflammation, complicating the reconstruction of periodontal tissue structures. Consequently, there is an urgent need to devise a novel strategy for managing diabetic periodontal conditions. Here, a multifunctional controlled‐release drug delivery system (GOE1) is developed by encapsulating self‐assembled nanoparticles (consisting of chlorhexidine acetate and epigallocatechin‐3‐gallate) into a hydrogel matrix composed of gelatin methacryloyl and oxidized hyaluronic acid. In vitro experiments demonstrate that the GOE1 hydrogel possesses good antimicrobial, antioxidant and anti‐inflammatory properties, and transgenic sequence genomics further illustrates that IL‐17‐producing RAW 264.7 macrophages are critical for mediating M1/M2 macrophage transition and provide favorable immune microenvironment. In addition, in vivo experiments reveal that GOE1 significantly ameliorates periodontal tissue inflammation and reduces the loss of alveolar bone by reducing inflammatory infiltration and collagen destruction. Overall, the GOE1 hydrogel offers a promising therapeutic option for managing diabetic periodontitis.