Abstract: X-ray fluorescence spectroscopy（XRF） passive detection technology has been widely used in coal quality detection with its excellent characteristics of fast analytical speed, nondestructive and wide range of analytical elements. Based on the research status of XRF, the development process, basic principle, analytical method, instrument structure and its classification, etc. of XRF are expounded in details. The mechanism of production, analysis principle of X-ray, the characteristics of qualitative analysis, semi-quantitative analysis and quantitative analysis are clarified. Moreover, the principle, composition, technical characteristics and application fields of different types of XRF spectrometers are compared and analyzed. The development and application of XRF in coal quality detection are analyzed. The result shows that the precision and accuracy could be obtained for analyzing the constant elements and trace elements in coal ash by using XRF spectrometer, when the samples are treated by both compression and melting production methods. The online XRF analysis technology is limited and influenced by the analysis principle, data model and environmental factors, which is mainly used for coal mines with low accuracy requirements of test results, raw coal production in coal preparation plant, quality control of the products and coal gangue identification. In view of the problems in the application process, the technical limitations of current XRF in coal quality detection are analyzed from four aspects: principle analysis, matrix effect, instruments and operation safety. Combined with the advantages and disadvantages of XRF, it is pointed out that XRF should be combined with other spectral or image technologies to broaden the range of measurable coal indicators. The accuracy and reliability of online or offline coal quality detection could be improved by combining “digital intelligence”, in order to provide analysis and testing technology and hardware foundation for helping the clean and efficient utilization of coal in China, and realizing the goal of smart industry as well as the carbon peaking and carbon neutrality goals.