A three-dimensional measurement apparatus , comprising: a projecting unit configured to project a patterned light onto a measurement target (OB); an image capturing unit configured to capture an image of the measurement target onto which the patterned light is projected, with an exposure time which is predetermined; and a calculation unit configured to extract a plurality of feature points included in the image and to calculate positions of a three-dimensional point group expressing a three-dimensional shape of the measurement target based on the plurality of feature points; and the three-dimensional measurement apparatus being characterized in further comprising: a determination unit configured to determine the exposure time or a light amount of the projecting unit such that at least one of a number of the plurality of feature points and a number of points included in the three-dimensional point group is at least a threshold that is defined based on either a maximum number of the plurality of feature points or a maximum number of points included in the three-dimensional point group, and the exposure time is shorter than an exposure time for the maximum number, wherein the plurality of feature points are feature points included in the patterned light and positions of the feature points on the image change according to the shape of the measurement target (OB). a projecting unit configured to project a patterned light onto a measurement target (OB); an image capturing unit configured to capture an image of the measurement target onto which the patterned light is projected, with an exposure time which is predetermined; and a calculation unit configured to extract a plurality of feature points included in the image and to calculate positions of a three-dimensional point group expressing a three-dimensional shape of the measurement target based on the plurality of feature points; and the three-dimensional measurement apparatus being characterized in further comprising: a determination unit configured to determine the exposure time or a light amount of the projecting unit such that at least one of a number of the plurality of feature points and a number of points included in the three-dimensional point group is at least a threshold that is defined based on either a maximum number of the plurality of feature points or a maximum number of points included in the three-dimensional point group, and the exposure time is shorter than an exposure time for the maximum number, wherein the plurality of feature points are feature points included in the patterned light and positions of the feature points on the image change according to the shape of the measurement target (OB). a determination unit configured to determine the exposure time or a light amount of the projecting unit such that at least one of a number of the plurality of feature points and a number of points included in the three-dimensional point group is at least a threshold that is defined based on either a maximum number of the plurality of feature points or a maximum number of points included in the three-dimensional point group, and the exposure time is shorter than an exposure time for the maximum number, wherein the plurality of feature points are feature points included in the patterned light and positions of the feature points on the image change according to the shape of the measurement target (OB). <EOS>