Maintaining frequency stability is a critical challenge in microgrid operations, especially in islanded mode. This study explores a novel approach to microgrid frequency regulation by leveraging coordinated bidirectional power flow between electric vehicles (EVs) and the grid through Grid-to-Vehicle (G2V) and Vehicle-to-Grid (V2G) modes. A simulation model comprising a synchronous generator and two battery banks of EVs—categorized by their state-of-charge (SOC)—is developed using MATLAB/Simulink. EVs with SOC < 80% engage in G2V charging, while those with SOC > 90% participate in V2G discharge during disturbances. When a 1 MW load is introduced at 10 s, the V2G group discharges energy to counteract the frequency drop. Conversely, at 30 s, a 2 MW load removal causes frequency overshoot, prompting V2G units to revert to charging mode, thereby re-stabilizing the system. The simulation confirms that intelligent coordination of EV charging and discharging effectively restores frequency within a tight band (0.999–1.001 p.u.). The proposed method enhances microgrid reliability, responsiveness, and resilience without the need for traditional frequency control assets. Future work will focus on optimizing EV scheduling strategies for large-scale deployment in frequency-sensitive environments.