This work reports a self-gelating alginate sponge (Alg-BA@PDA) engineered by introducing 3-Aminobenzeneboronic acid groups and polydopamine nanoparticles. Hydroxyl groups on alginate chains dynamically crosslink with BA to form boronate ester networks, enabling rapid in situ gelation and conformal wound coverage. PDA-NPs endows the sponge with photothermal activity, antibacterial function, and ROS scavenging capacity, while also mitigating nanoparticle cytotoxicity through controlled release. Together, these features suppress inflammation, enhance angiogenesis, and promote collagen deposition. In vivo, the multifunctional Alg-BA@PDA sponge markedly accelerates full-thickness skin wound healing, highlighting its promise as a next-generation wound dressing.