A method of semiconductor overlay measuring includes following operations. Provide a test substrate. Conductive structures are located in the test substrate and exposed from a top surface of the test substrate. Positioning the test substrate to a standard position and capturing a first image of the top surface of the test substrate. Mark first marks corresponding to the exposed conductive structures on the first image. Form a test capping layer with capacitor openings on the top surface of the test substrate. Move the test substrate to the standard position and capturing a second image of a top surface of the test capping layer. Identify the capacitor openings on the second image with second marks. Compare the first marks with the second marks to determine a position offset between the test substrate and the test capping layer.