Abstract: Smart responsive nanocarriers have emerged as a promising strategy for tumor therapy, demonstrating significant clinical potential due to their high targeting capability and excellent biocompatibility. An amphiphilic copolymer, poly(propylene sulfide)-poly(3-acrylamidophenylboronic acid-co-poly(ethylene glycol) methyl ether methacrylate) (PPS_k-P(APBA_m-co-OEGMA_n)), was designed and synthesized. Through self-assembly, reactive oxygen species (ROS)-responsive polymeric micelles were obtained. The hydrophilic P(APBA_m-co-OEGMA_n) shell was further crosslinked using the polyphenolic drug proanthocyanidin (PC), forming a boronate ester covalent network that enhanced the stability of the nanocarrier while introducing pH responsiveness, and yielding dual pH/ROS-responsive microgel carriers. The particle size, surface morphology, and crosslinking behavior of the microgels were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), and ultraviolet-visible (UV-Vis) spectroscopy. The drug loading and release behaviors of small-molecule doxorubicin (DOX) and macromolecular bovine serum albumin (BSA) were investigated, demonstrating efficient drug encapsulation and stimulus-responsive release. The results confirmed that the nanogel carrier exhibited pH/ROS dual responsiveness, stable independent loading of multiple drugs, and controlled drug release. This study provides a scientific foundation for precise drug delivery, intelligent release systems, and overcoming multidrug resistance in cancer therapy.