Disclosed are a displacement sensor-combined electrostatic measurement potential sensor, and an operation method therefor, wherein a displacement sensor and an electrostatic measurement potential sensor are provided in one device, and operations thereof are linked; a distance to an electrified body measured by the displacement sensor is stored in a main controller to automatically correct a measurement value of the amount of static electricity obtained by the potential sensor; a change in capacitance that the displacement sensor affects with respect to the potential sensor is applied to correction of an error in a result value measured by the potential sensor, so that it is possible to solve the problem of malfunction according to detection of the electrified body, wherein the distance thereto is changed, and accurately measure the potential; and by manufacturing the device in a small size, easy use is achieved and manufacturing and installation costs are reduced.