Abstract: By analyzing the monochromatic X-ray backlighting system with spherically bent crystal, the expressions for the spatial resolution and the spectral resolution of this system are deduced, and the relationship between these key performance parameters and the design parameters of the system is analyzed. Analysis results of the imaging system with different imaging modalities are obtained, which coincide with the ray tracing results. A demo test of the monochromatic imaging system was operated on the X-ray source, and the results are consonant with the simulation and the calculation. This diagnosis could have a broad prospect of application in the measurements on Shenguang laser facility.