There are still some ambiguities on the surface-enhanced Raman scattering (SERS) of Al surfaces. In this work, some experimental results for normal Raman scattering and resonance Raman scattering from p-nitrobenzoic acid (PNBA), Rhodamine 6G and dye 1555 adsorbed on substrates of metal Al and aluminum oxide are reported. We used the techniques of dipping, immersing and spinning to deposit molecules on substrates which were produced by lithography or mechanical polishing. All the results show that there is no enhancement for the molecules on these surfaces. The observed Raman bands from PNBA adsorbed on a substrate of lithographically produced Al were from bulk molecules of PNBA. The results are well explained by the antenna resonator model of SERS.