Dysregulated copper ion homeostasis is a key factor in disrupting the immune microenvironment of diabetic wounds. However, conventional copper delivery systems are limited by unstable release kinetics and transient therapeutic effects. To address these challenges, this study introduces a long-acting copper ion-releasing hydrogel (GelMA@HKUST-1) based on a metal-organic framework (HKUST-1), designed to promote diabetic wound healing by modulating neutrophil function. In vitro analysis demonstrated that copper ions released from the hydrogel significantly suppressed hyperglycemia-induced neutrophil extracellular trap (NETosis) formation, while restoring immune function through the promotion of neutrophil apoptosis. In antibacterial assays, although the hydrogel exhibited limited direct bactericidal activity, it effectively reduced bacterial burden and enhanced host immune defense by inhibiting NETosis and accelerating neutrophil apoptosis. Additionally, in vivo studies revealed that the porous structure of HKUST-1 enabled sustained copper ion release for over one week, significantly accelerating wound healing in diabetic mice without causing systemic toxicity. This study proposes a dual regulatory mechanism for copper-mediated immunomodulation—balancing NETosis inhibition and apoptosis activation to optimize antibacterial efficacy—providing a novel therapeutic strategy with prolonged action and improved safety for diabetic wound management.