<p>Self-healing anticorrosive coatings are essential for extending the lifespan of metallic materials in aggressive environments. This study presents a novel sandwich-structured coating composed of a polydopamine (PDA) inner layer, a ZIF-67 electroplated interlayer, and MXene/CNTs fillers incorporated into a waterborne acrylic epoxy (EA) matrix. The PDA layer enhances adhesion, while the ZIF-67 interlayer functions as an active inhibitor reservoir that responds to pH changes, releasing Co²⁺ and 2-methylimidazole to promote defect repassivation and self-healing. The outer MXene/CNTs layer significantly improves barrier properties by forming a tortuous path for corrosive agents and enhancing interfacial stability. Compared with single-component coatings, the sandwich-structured composite coating exhibited markedly enhanced corrosion resistance in harsh acidic environment, with an obvious increase in corrosion potential. Moreover, a high <i>R</i>_ct value of 1.79 × 10^5&#xa0;Ω cm² was maintained by this coating even after 30 days of service, evidencing its durable protection. Under scratched conditions, the coating exhibits efficient self-healing, recovering its impedance and repassivating defects. This work demonstrates the synergistic benefits of the PDA/ZIF-67/MXene system, offering an effective solution for long-term corrosion protection with self-healing properties, suitable for various engineering applications.</p>