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A Schwarzschild microscope working at 13.5 nm was developed.According to the theory of a coaxial two-mirror system,the optical structure of Schwarzschild objective was designed by eliminating third-order spherical aberrations,coma and astigmatism.Experiments show that the spatial resolution of the designed objective achieves 550 lp/mm within the field of ±0.3 mm with respect to the calculation of modulation transfer function.Based on the working wavelength and incidence angle of lights,the Mo/Si multilayer optics with the reflectivity of 61% at 13.5 nm was designed and fabricated.In order to remove visible and ultraviolet lights,a filter with materials of Zr,Si and Si3N4 was designed and fabricated,and the transmittance of 21.1% was obtained at 13.5 nm.With the purpose of demonstrating the resolution of microscope,the 60 lp/mm grid backlit by laser produced plasma was imaged via the Schwarzschild microscope on a Charge Coupled Device(CCD),and the results show that the imaging system can offer the resolution of 3 μm in the 0.5 mm field.It concludes that the resolution of imaging experiment is limited by the resolution of CCD camera.