Provided is a chromatic confocal sensor including: a light source section that emits a plurality of light beams having different wavelengths; an optical head that includes an objective lens that converges the plurality of light beams at different focal positions and selects, as measurement light, light reflected by an object to be measured at the focal position out of the plurality of light beams; a spectroscope including diffraction gratings that split the selected measurement light into a plurality of diffracted light beams and a sensor that receives two or more of the plurality of diffracted light beams; and a signal processing/control section that calculates a position of the object to be measured based on a difference between light reception positions of the two or more diffracted light beams received by the sensor.