In the spectroscopic analysis of minor and trace elements by fluorescent X-rays, many improvements in the analytical performance of trace element measurements have been made. For the analysis of trace elements, the background intensity governs the analytical accuracy and the lowest detection limit in a sample. A comparison is made between experimental and theoretically calculated background X-ray intensities in a previous paper. It is based on the formula for scattered X-ray intensity, from the estimation of Thomson and Compton scattered X-rays. Also, the asymmetrical peak profiles at the base of the giant intensity peak are discussed and are clearly shown in the skirt part of K beta X-rays, e.g. , Ni-K beta or Fe-K beta X-rays. The purpose of this report is to investigate the intensity of background X-rays, using glass beads and powder samples of iron oxide and quartz, based on the previous fundamental studies and the overlapping correction procedure for cobalt determination in low-alloy and stainless steel.