Introduced the theoretical model of laser feedback interferometry, explaining the technical characteristics such as high sensitivity, simple device structure, self?aligning, and the ability to achieve precise measurements of non?cooperative targets. The advantages of laser feedback measurement and traditional interferometric measurement methods were discussed. Explored various applications of laser feedback measurement in industrial and research domains, including displacement measurement, angle measurement, vibration measurement, and absolute distance measurement. It is pointed out that the use of structures like harmonic reuse, frequency reuse, polarization reuse, and full?path coherent combining can enhance the application performance of feedback measurement. Finally, the future development direction of laser feedback technology is discussed, providing reference for promoting the widespread application of feedback technology.