The molecular-beam-epitaxial-grown short-period strained-layer Si/Si1-xGex superlattices were examined by Raman spectroscopy. By using several excitation sources, the Raman depth probe reveals the phonon signals from the virtual substrate, the Si1-xGex alloy of superlattices, strained Si-layer of superlattices, and unstrained Si-substrate separately. The Ge composition of virtual substrate and Si1-xGex alloy of superlattices can be determined, and the degree of relaxation of virtual substrate and strained Si-layer are found as well. On the basis of the results of strain examination and consideration for the influence of the band structure, we know that the band structure of the sample belongs to type-II band alignment. It gives the preliminary explanation about the source of exciton transition observed from Magneto-optics spectra.