Based on the Purkinje system and the anatomically detailed ventricular geometry of a human heart, an integrated 3D human ventricular conduction model is proposed to simulate the reentry wave propagation for studying the generation mechanism of ventricular fibrillation caused by early afterdepolarizations. This model was simulated the cardiac cell electrical activity of early afterdepolarizations and the susceptibility to early afterdepolarizations of three kinds of cells. Then, the influence of cells which is susceptibility to early afterdepolarizations on the reentrant spiral wave dynamics was analyzed. Finally the ECG waveform under ventricular fibrillation caused by early afterdepolarizations was quantified. The experimental results showed that the middle cells are most likely to generate early afterdepolarizations. With generating early afterdepolarizations in middle cells, the reentrant wave would be broken up and the ECG waveform would be disordered and irregular, which was in agreement with the results obtained on animal models. Therefore, it may be an important target for inducing ventricular fibrillation.