Abstract: The present disclosure relates to a method for determining initiation positions of fretting fatigue cracks. The processed inner circular hole test workpiece is placed on a stage of an optical microscope, wherein the inner hole surface to be measured is perpendicular to the scanning beam direction of the microscope; measurement is performed along the real contact orientation between the inner hole surface of the inner circular hole test workpiece and the pin shaft. From the measured surface morphology and profile image, rectangular target areas with a coverage rate of 75%˜90%, and the amplitude distribution function, surface skewness and surface kurtosis values of the respective surface profiles are extracted from the target areas. By comparing the positive/negative of and the magnitude of the skewness and kurtosis values measured in the target areas, the side where the initiation position of fretting fatigue cracks is located can be determined.