Surgical resection is the primary treatment for breast cancer, but tumor recurrence due to residual cells and a postoperative microenvironment remains a critical challenge. We present a multifunctional therapeutic hydrogel (Apt-Au@Gel) integrating ROS scavenging, VEGF capture, and photothermal therapy (PTT) to suppress postsurgical tumor recurrence. Apt-Au@Gel consists of a crosslinked polymeric phenylboronic acid (pPBA) and polyvinyl alcohol (PVA) loading VEGF split aptamer-gold nanoparticles (Apt-AuNPs). Upon exposure to elevated ROS, released Apt-AuNPs aggregate to enable VEGF capture and enhance photothermal effects. Apt-Au@Gel implantation at the surgical site significantly inhibited tumor recurrence without systemic toxicity. These results suggest that Apt-Au@Gel offers a synergistic strategy for effective postsurgical cancer therapy by modulating the postoperative tumor microenvironment and eliminating residual tumor cells.