Owing to their reduced weight, size, and high electronic-optic conversion efficiency, rare earth (RE) doped active fiber lasers or amplifiers are crucial in space-based applications, such as space laser communication, space laser radar, and space waste disposal and military. However, the radiation-induced attenuation of the active (RE-doped) fibers is approximately 1000 times larger than that of passive (RE-free) fibers under the same radiation condition, which poses a severe challenge to the long-term stability of active fiber lasers or amplifiers in space. First, this study briefly introduces the space radiation environment, the application requirements and challenges of silica-based optical fibers in space. Second, the latest research progress in the field of radiation-resistant active fibers, both in China and elsewhere, are systematically introduced from three aspects: 1) the mechanism of radiation-induced darkening of active fibers; 2) the primary factors influencing the radiation resistance of active fibers; 3) the methods to improve the radiation resistance of active fibers. Finally, the potential issues that require further investigation are suggested.