The high-energy X-ray source generated by ps-laser driven microwire target has excellent characteristics of micro-focus, high brightness and high spatiotemporal resolution, and it has become an important diagnostic method to investigate the dynamic response process of substances under extreme conditions. X-ray source generated by the radiation of the end face of the filament target with a low-density and low-Z substrate for backlighting, which is limited by the influence of material self-absorption and electron recirculation effect on the X-ray radiation intensity, resulting in the weakening of the bremsstrahlung intensity of the filament target end face, hence we designed the X-ray backlighting experiment of static step wedge object generated by ps-laser irradiation self-sustaining independent filament target lateral bremsstrahlung line. The experiment was carried out on on the vacuum target chamber of the picosecond laser beam of the XGIII laser facility of China Academy of Engineering Physics. The ps laser was incident 30? away from the target normal with 10μm diameter molybdenum wire and gold wire target as X-ray light source, and 3?3 array pinhole camera with PIXIS-XB CCD was in the direction of laser reflection to measure X-ray focal spots.The results showed that the minimum transverse size of the obtained X-ray source focal spot was about 20 μm, the longitudinal size reached 10 μm, and the optimal spatial resolution of static X-ray backlight radiography was close to ~11 μm, which was comparable to the diameter of the microwire target. The experimental results showed that the self-sustaining independent silk target side can obtain a highly penetrating micro-focus X-ray source, and the spatial resolution consistent with the backlight radiography of the filament target end face could be obtained, which could provide a reference for research applications such as dynamic process diagnosis of high-energy density substances.