The function and influence of the corner effect in groovedgate MOSFET is simulated using classical twodimensional device simulator PISCESⅡ. The electric field of the channel in groovedgate metalorganic semiconductor field effect transistor(MOSFET) and impact on the threshold and hot carrier effect are studied. The corner effect is very favorable to suppressing short channel effects and hot carrier effects. The impact of corner effect on groovedgate MOSFET is changed with the change of the corner, and is the largest at about 45°. Therefore， the groovedgate MOSFET has a very great application prospect in deep submicro device architecture.