The fabrication process is carried out for the absorption grating, which is a core device in the X-rayphase-contrast imaging technology, Tungsten nanoparticles are used as the X-ray absorption material, withethanol and the emulsifier Op-10 being used as cariers. Tungsten nanoparticles are filled into the gratingstructures by means of free deposition,By studying the influenee of difierent partiele sizes on the filling efiect , itis found that the filling efeet of tungsten nanoparticles with an average size of approximately 50 nm is betterthan that of partieles with a partiele size of 200 nm,ln addition,in order to compare the influence of differentabsorption materials on the quality of absorption gratings , tungsten and bismuth nanoparticles with an averageparticle size of approximately $0 nm are filled into the grating struetures, and their induced X-ray absorptioncontrast are compared.lt is found that the contrast of the tungsten grating is approximately 5096 ,and that of thebismuth grating is approximately 4196, Tungsten partieles are more suitable than bismuth for fabricatingabsorption gratings.Filling grating, structures by the free deposition of metal nanoparticles is a low-cost methodand allows for the fabrication of large-period gratings.