The present invention provides a three-dimensional shape measuring device and a sensor employed for the three-dimensional shape measuring device. The three-dimensional shape measuring device comprises a light source for scanning plane light over the surface of an object, an image sensor opposed to the object and provided with a plurality of pixels, an optical system for forming an image of a bright line appearing on the surface of the object due to plane light on the image sensor, a plurality of capacitors installed in association with pixels of the image sensor, a charger for storing given charges in a plurality of capacitors before plane light scanning starts, a plurality of dischargers lying in association with capacitors and gradually discharging the capacitors for pixels corresponding to a bright line image from when plane light scanning starts until the bright line image passes through the pixels, and an arithmetic logic means for computing charges remaining in the plurality of capacitors after plane light scanning is completed and thus providing a three-dimensional shape of an object. Thereby, a three-dimensional shape of an object can be measured at a high speed with high precision.