Abstract: A solid catalyst component for olefin polymerization includes magnesium, titanium, a halogen, a poly(?-olefin), and an internal electron donor. A Ti2p spectrum obtained from XPS analysis of the solid catalyst component is subjected to peak separation by means of Gaussian-Lorentzian peak-separation fitting. The result of the peak separation shows that the spectrum peaks of the Ti2p3/2 orbit have at least three characteristic peaks at positions where an electron binding energy is 459.9-454.9 eV. The solid catalyst component, when used in olefin polymerization, has the characteristics of slow decay of activity with the increase of storage time and a low fine powder content of the resulting polymer.