An electronic model of the coronary vessel consisting of resistor, capacitor and Field Effect Transistor (FET) is proposed in order to perform a dynamic simulation of the left coronary circulation and to clarify its mechanisms. Based on this model, an equivalent circuit of the coronary circulation is constructed that is divided into subepicardial and subendocardial layers and consists of segments of artery, arteriole, capillary, venule and vein for both the layers. In this simulation, the observed flow waveform of the left main artery showed dominance of flow in diastole as compared to that in systole. In epicardium, inverse venous flow was observed in early systole. These simulated waveforms are similar to those in real left coronary circulation observed by physiological and clinical researchers. Among all the segments of intramyocardium, only the venules were found to possess a time-varying resistance characteristics. From the results of this study, it is considered that the combination of resistance and capacitance of the vessel acts as an integrator and a differentiator for blood pressure and intramyocardial pressure, respectively and that the effects of integration of blood pressure and differentiation of intramyocardial pressure play a very important role in determining the factors influencing the left coronary circulation.