The invention discloses a method of obtaining a cam contour shape of an object, which uses a video camera for shooting the measured object continuously to get a series of object images. After the object image and a background being segmented, a contour image of the object in a visual angle of every video camera can be obtained. A plurality of object marginal points are arranged on each height of each external contour image; the marginal points and a center of the video camera constitute a section plane. The section plane intersects with the measured object to obtain a cross-section of the object. After the cross-section of the object is processed by a computer, the contour of the object on the cross-section can be obtained, which is called as a residual plot of the object on the cross-section. After all contours of the cross-sections of the object are obtained, a spatial superpose of the object contour is made along the height direction to get an intact three-dimensional model of the object. The method of obtaining the object shape with the cam contour provided by the invention can obtain a plurality of scanning spots, and has the advantages of fast scanning speed, safe and reliable usage, wide scanning range, thereby not only being applied to small-size situation, but also scanning the object with larger size.