Abstract: High-power ytterbium-doped fiber lasers have a wide range of applications in the maintenance of nuclear facilities owing to the advantages of high power, high efficiency, and flexible transmission. However, the irradiation effect in the nuclear facility environment can decrease the power of the fiber laser, which poses a big challenge to applications in such scenarios. Considering the self-bleaching effect of fiber lasers, we explore the relationship between darkening and self-bleaching effect under different irradiation dose rates. When the irradiation dose rate is relatively low, such as 0.1 rad/s, the output power of the 1 kW fiber laser is quite stable with the power fluctuation less than 1.79% during the whole experiment. We name such phenomenon as the self-bleaching and radiation equilibrium (SBRE). It is verified for the first time that under a certain irradiation dose rate, the laser power enhancement caused by the self-bleaching effect of the fiber laser can balance the power decrease caused by the irradiation effect, which provides effective support for the design of fiber lasers in related applications.