An apparatus for controlling oil pump pressure includes a sensor for sensing knocking of an engine, an oil pump configured to determine a pressure for discharging engine oil toward a piston of the engine, and a control unit configured to control the pressure of the engine oil discharged toward the piston by determining whether the knocking occurs based on a parameter transmitted from the sensor for determining whether the knocking occurs, and by controlling the oil pump based on whether the knocking occurs in the engine.