光纤激光器的输出功率达到一定的阈值后，激光器中会出现模式不稳定效应，对激光器的输出功率和光束质量造成严重影响，限制了大功率激光器的进一步应用，因此研究大功率光纤激光器中的模式不稳定机理和抑制方法对光纤激光器输出功率的进一步提升具有重要意义。本文系统介绍了模式不稳定的机理并总结了一些模式不稳定的抑制方法。 After the output power of the fiber laser reaches a certain threshold, the mode instability occurs in the laser, which seriously affects the output power and the beam quality of the laser, which limits the further application of the high power laser. Therefore, the mode of the high power fiber laser The instability mechanism and the suppression method are of great significance to the further improvement of the output power of the fiber laser. This paper systematically introduces the mechanism of mode instability and summarizes some mode-based suppression methods.