A three-dimensional measuring device is a three-dimensional measuring device that performs three-dimensional measurement of an object using a laser beam. The three-dimensional measuring device includes a laser emitter disposed in a movable section of a robot and configured to irradiate a region including the object with the laser beam, a laser emission controller configured to control driving of the laser emitter, an image capturing device configured to image the object, on which the laser beam is irradiated, and acquire image data, and a point cloud generator configured to generate, based on the image data, three-dimensional point cloud of the region including the object. The laser emitter includes a laser beam source and a diffuser configured to diffuse the laser beam emitted from the laser beam source.