Abstract: In this paper, we discuss the experiment conducted onLF-11 laser facility. The aim is to study the irradiation damage of X -ray reflction mirrors that were used in the double -pass amplification experiment of Ne-like Ge X -ray lasers . The results indicated that the mirror's life time was 440ps when it was irradiated by 113MW/cm² X rays and 227 MW/cm² scattered laser light. When the intensities of X rays and scattered laser light on the mirror were 50 MW/cm² and 101 MW/cm², respectively, the mirror's life time was 700ps.