The photoluminescence (PL) properties and the surface morphologies of the porous silicon (PS) prepared from the wafers whose front sides were coated with or without Al film were studied. Furthermore, the Fourier Transforms Infrared (FTIR) and the Raman spectra were carried out. By introducing the Al film onto the front side of the wafer before the anodic etching, the surface morphology of the PS was quite different from that of conventional PS, which can be explained by the formation mechanism of the PS. The different PL properties of the PS may be attributed to the discrepancy in the structural configuration of the samples.