Provided are a three-dimensional measurement device and three-dimensional measurement method capable of reducing measurement time for height measurement using a phase shift method. A substrate inspection device 1 is provided with an illumination device 4 for irradiating a prescribed optical pattern from a diagonally upward position onto the surface of a printed circuit board 2, a camera 5 for imaging a portion of the printed circuit board 2 irradiated with the optical pattern, and a control device 6 for carrying out various control, image processing, and calculation within the substrate inspection device 1. The control device 6 uses the relationship between the gain and offset of an optical pattern determined by prescribed imaging conditions and a gain or offset value of the optical pattern that is for coordinates to be measured on image data and is determined from brightness values at the coordinates to be measured to measure the height of the coordinates to be measured using a phase shift method on the basis of two sets of image data imaged under optical patterns with two shifted phases.