Abstract: A novel method of cylindrical curved crystal inspection is presented utilized the X-ray tube as the light source and the CMOS detector coated scintillator fibre faceplate as the on-line recorder. According to the design of the high accuracy coaxial turntable, the whole cylindrical curved crystal surface is converted into several line segments to be detected separately, and the arrangement of optical paths and the position shift of spectral lines are calculated analytically. The iron target X-ray tube (the wavelength of K_β feature spectral line is 0.193 6 nm) is selected as the experimental light source. The iron material X-ray tube is chosen as the X-ray source. The sample is quartz cylindrical curved crystal with the 120 mm radius of curvature. The feature spectral lines of Fe-K_α and Fe-K_β are observed clearly. The Fe-K_α spectral line is shifted 96 μm through analyzing image of 9 sample locations on the cylindrical curved crystal. The deviation of the radius is 40 μm and ΔR/R is 0.033%. It shows that the sample was curved in high accuracy. The tested cylindrical curved crystal has been applied on the experiments carried on the large laser facility and the high performance spectral data is acquired. It demonstrates that the method of curved crystal inspection is available and useful.