Absorption and scattering properties of monoenergetic X rays of 30 keV-110 keV in iron have been studied with Monte Carlo method. The angular distributions of scattered photons and the spectra of backscattered radiation are presented. The results show that the backscattered radiation is primarily the characteristic X radiation of iron for the incident X rays of low energy, and that with the energy of incident X rays increasing, the backscattered radiation of high energy increases and the characteristic X radiation decreases rapidly.