Nanofillers are considered the most aspiring materials in recent years for the anti-corrosion functional coatings applied to the metal surface. Herein, the CaFe-tolyl-triazole layered double hydroxide (CaFe-TTA LDH) nanoplates and CaFe-tolyl-triazole layered double hydroxide@graphitic carbon nitride (CaFe-TTA LDH@g-C3N4) nanohybrids were successfully prepared using the facile approaches. The prepared CaFe-TTA LDH nanoplates/CaFe-TTA LDH@g-C3N4 nanohybrids were incorporated into the epoxy resin to develop corrosion-resistant nanocomposite coatings. The resistances at 0.01 Hz (|Z|0.01) of EP/CaFe-TTA LDH and EP/CaFe-TTA LDH@g-C3N4 samples were reduced by one order of magnitude after 60 days of immersion in 3.5% NaCl solution (from 5.49 × 108 Ω cm2 to 4.42 × 107 Ω cm2 and from 1.18 × 109 Ω cm2 to 2.25 × 108 Ω cm2 respectively), compared to the pristine EP coating, which decreased approximately two orders of magnitude (from 2.61 × 108 Ω cm2 to 7.69 × 106 Ω cm2). The localized electrochemical impedance spectroscopy (LEIS) and salt spray tests further explored the self-healing activity of the coatings and revealed that the scratched EP/CaFe-TTA LDH@g-C3N4 coatings maintained excellent corrosion resistance. The pull-off adhesion test showed an improved adhesion strength as compared to the pristine epoxy coating. Moreover, the density functional theory simulation confirmed the reaction mechanism of the nanofillers during the corrosion process. Hence, the results revealed that the EP/CaFe-TTA LDH@g-C3N4-based coatings delivered superior barrier/active inhibition performance due to the labyrinth and self-healing effect of nanofillers, suggesting a promising avenue for the development of a variety of nanocomposite coatings for various functional applications.