<p>Tidal current energy is a promising renewable energy resource; however, conventional tidal current generators based on mechanical gearboxes suffer from large volume, low efficiency, and high maintenance requirements. To address these issues, this paper proposes a modulation-enhanced single-ring dual-modulation axial magnetic gear generator (MEAMG) for tidal current energy applications. The proposed topology employs a single modulation ring to simultaneously realize sum-and-difference magnetic field modulation, establishing a radial–axial dual-modulation magnetic coupling mechanism that enhances magnetic field modulation capability and suppresses magnetic leakage. In addition, the armature stator is integrated into the magnetic gear structure, resulting in a compact configuration and improved power density. Finite element analysis is conducted to evaluate the electromagnetic performance of the proposed MEAMG. The results show that the average torque of the low-speed rotor increases by 37.5%, while the high-speed rotor torque increases by 22% compared with the conventional AMG structure. Moreover, the proposed MEAMG exhibits significantly higher back electromotive force and load current amplitudes than the conventional AMG. The proposed MEAMG achieves an operating efficiency of approximately 81% under resistive load conditions, demonstrating superior electromagnetic performance and energy conversion capability. These results indicate that the proposed topology is suitable for compact low-speed renewable energy generation systems such as tidal current and marine energy conversion applications.</p>