Abstract: A process for measuring the contour configuration of an article defined by numerous cylindrical surface portions, is disclosed, which process comprises placing the article on a turntable, irradiating parallel light beams upon one side portion of the article while rotating the turntable, detecting changes, as a function L(.theta.) by means of a light-receiving member, in locations L at which the parallel light beams are interrupted by the article, said .theta. denoting a rotational angle of the turntable, inputting data of L(.theta.) thus detected into a memory of a computer, calculating a value of L(.theta.)+L(.theta.180.degree.), comparing the thus calculated value with that for an ideal contour configuration, and correcting deviations in a position and angle of the article. Thereby, a correct measured value is obtained.