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 ofimage 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) istransported a predetermined amount are added to each coordinate position of the printed circuit board (1), and the average value thereof is calculated.