A method for detecting occlusal force comprising: a grounding step of grounding a plurality of X-electrodes and a plurality of Y-electrodes of a sensor sheet at a ground potential, wherein the sensor sheet includes a pressure-sensitive film, the plurality of X-electrodes formed on one surface of the pressure-sensitive film, and the plurality of Y-electrodes formed on the other surface of the pressure-sensitive film and extending perpendicular to the plurality of X-electrodes, a specific address range identifying step of holding sequentially one electrode group of the plurality of X-electrodes and the plurality of Y-electrodes of the sensor sheet at the ground potential, while detecting a potential of each electrode of the other electrode group of the plurality of X-electrodes and the plurality of γ-electrodes to identify a specific address range defined by electrodes where a potential equal to or greater than a predetermined potential has been detected (S404; S405; 8406); a scan address area identifying step of scanning first intersection points between an electrode group where the potential equal to or greater than the predetermined potential has been detected among the plurality of X-electrodes in the specific address range identifying step and an electrode group where the potential equal to or greater than the predetermined potential has been detected among the plurality of Y-electrodes in the specific address range identifying step to identify a scan address area defined by second intersection points where predetermined relative potentials between X-electrodes and Y-electrodes are to be detected; and a relative potential detecting step of detecting relative potentials between X-electrodes and Y-electrodes of the second intersection points included in the scan address area. a grounding step of grounding a plurality of X-electrodes and a plurality of Y-electrodes of a sensor sheet at a ground potential, wherein the sensor sheet includes a pressure-sensitive film, the plurality of X-electrodes formed on one surface of the pressure-sensitive film, and the plurality of Y-electrodes formed on the other surface of the pressure-sensitive film and extending perpendicular to the plurality of X-electrodes, a specific address range identifying step of holding sequentially one electrode group of the plurality of X-electrodes and the plurality of Y-electrodes of the sensor sheet at the ground potential, while detecting a potential of each electrode of the other electrode group of the plurality of X-electrodes and the plurality of γ-electrodes to identify a specific address range defined by electrodes where a potential equal to or greater than a predetermined potential has been detected (S404; S405; 8406); a scan address area identifying step of scanning first intersection points between an electrode group where the potential equal to or greater than the predetermined potential has been detected among the plurality of X-electrodes in the specific address range identifying step and an electrode group where the potential equal to or greater than the predetermined potential has been detected among the plurality of Y-electrodes in the specific address range identifying step to identify a scan address area defined by second intersection points where predetermined relative potentials between X-electrodes and Y-electrodes are to be detected; and a relative potential detecting step of detecting relative potentials between X-electrodes and Y-electrodes of the second intersection points included in the scan address area.