The wound healing process consists of four continuous and overlapping stages-hemostasis, inflammation, proliferation, and remodeling-involving a variety of cells, growth factors, and the extracellular matrix. In recent years, growing evidence has shown that enhancing endogenous hydrogen sulfide (HS) synthesis or providing exogenous HS can promote angiogenesis, inhibit inflammation, reduce excessive oxidative stress, and support collagen deposition. However, the administration of exogenous HS often presents challenges related to controlling its release duration and achieving targeted delivery. To achieve controlled and site-specific delivery of HS to the wound area, a dual-network cross-linked injectable hydrogel formed by grafted ε-poly-L-lysine (designed as EG) and oxidized dextran (OD) (EGODF) loaded with a hydrogen sulfide donor (HSDF-NH) to study its potential in wound healing is developed. The hydrogel exhibits excellent injectability, self-healing capability, and mechanical strength. Upon reactive oxygen species (ROS) stimulation, HSDF-NH releases both self-reporter fluorescence (HSDG-NH) and HS. Changes in the self-reporter fluorescence signal reflect HS production and its entry into the body to exert therapeutic effects. Finally, using a wound model and a hypertrophic scar repair model, it is demonstrated that EGODF hydrogel is effective in promoting wound healing and inhibiting scar production.