A three-dimensional measurement system, comprising: a projector configured to project patterned light onto a target object; a first camera configured to image the target object; a second camera configured to image the target object from a viewpoint different from the first camera; and an image processor configured to process a first image received from the first camera and a second image received from the second camera to obtain three-dimensional information about the target object, the image processor including a first measurer (21, 111) configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer (22, 116) configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, wherein the patterned light has a combined pattern combining a spatially encoded pattern and a random pattern, the spatially encoded pattern includes a plurality of unit elements arranged regularly, each of the plurality of unit elements is an area corresponding to a depth value, and the random pattern includes a plurality of random pieces arranged randomly. a projector configured to project patterned light onto a target object; a first camera configured to image the target object; a second camera configured to image the target object from a viewpoint different from the first camera; and an image processor configured to process a first image received from the first camera and a second image received from the second camera to obtain three-dimensional information about the target object, the image processor including a first measurer (21, 111) configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer (22, 116) configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, a first measurer (21, 111) configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer (22, 116) configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, wherein the patterned light has a combined pattern combining a spatially encoded pattern and a random pattern, the spatially encoded pattern includes a plurality of unit elements arranged regularly, each of the plurality of unit elements is an area corresponding to a depth value, and the random pattern includes a plurality of random pieces arranged randomly.