In this study, the X-ray attenuation properties of electrospun nanoparticles (n)-Bi2O3/epoxy-polyvinyl alcohol (PVA) nanofiber mats with different filler loadings of n-Bi2O3 were compared as a function of X-ray tube voltages (40-100 kV) using a general radiography unit. It was found that the X-ray attenuation by the electrospun n-Bi2O3/epoxy-PVA nanofiber mats increased with the increment of filler loading except for the nanofiber mat with 12 wt% of n-Bi2O3 filler. This indicated that the nanofiber mat presents the lowest X-ray attenuation properties compared to the others with another filler loading. The result was explained by cross-sectional scanning electron microscopy (SEM) image, which revealed that the 12 wt% of electrospun n-Bi2O3/epoxy-PVA nanofiber mat has the highest amount of porosity compared to the other samples.