A method and an apparatus are provided to measure a position of a mark with a less measurement error caused by a variation in a wafer process condition. The mark is illuminated with light and an image of the mark is formed, via an optical system, in a light receiving surface of a sensor. The image of the mark is sensed and image data thereof is acquired by the sensor. Correction data of a fundamental frequency and a high harmonic of the image data is set based on information associated with a shape of the mark, an imaging magnification of the optical system, and an imaging area of the sensor. The image data is corrected using the correction data, and the position of the mark is calculated using the corrected image data.