Provided is a three-dimensional measurement device with which it is possible to dramatically improve measurement accuracy when performing three-dimensional measurements utilizing a phase shift method. A substrate inspection device 10 includes: a conveyor 13 that transports a printed circuit board 1; an illumination device 14 that illuminates the surface of the printed circuit board 1 with a predetermined light from diagonally above; and a camera 15 that images the printed circuit board 1 illuminated with said light. When acquiring at least one set of image data among four sets of image data necessary for performing a three-dimensional measurement according to a phase shift method, the continuously transported printed circuit board 1 is illuminated with a striped pattern having a light intensity distribution with a rectangular waveform or a trapezoidal waveform. The brightness values of multiple instances of image data captured each time the printed circuit board 1 is transported a predetermined amount are added to each coordinate position of the printed circuit board 1, and the average value thereof is calculated.