Abstract: Quantitative analysis of trace asbestos (mass fraction as low as 0.1%) is a worldwide problem. A method for the quantitative determination of trace asbestos with mass fraction of 0.1%~5.0% weigh in friction materials such as bicycle and electric vehicle brakes by X-ray diffraction system was developed. The base standard absorption amendment method was used for quantitative determination of traces asbestos in the samples and then the ratio of asbestos was calculated. This method has been applied to the quality inspection of exported bicycles and electric vehicles