Traumatic brain injury (TBI) is a common clinical disease, and the current hyperbaric oxygen and hypothermia therapy are suboptimal. Traumatic brain injuries were accompanied by acute inflammatory reactions, brain edema, neuron damage, and the destruction of blood–brain barrier. Herein, curcumin-loaded lysine/poly(ethylene glycol) diacrylate (PEGDA) hydrogels were constructed via Michael addition for traumatic brain injury treatments. The curcumin-loaded lysine/PEGDA hydrogels were injected into brain injury defect sites with complex anatomical and irregular structures. The real-time therapeutic effects of the curcumin-loaded hydrogels were evaluated by magnetic resonance imaging (MRI). Curcumin-loaded hydrogels can inhibit the inflammatory reaction and promote nerve repair. The curcumin-loaded hydrogel could provide a promising strategy for traumatic brain injury treatments.