In this work, an interesting phenomenon demonstrating the similarities between the results from both Surface Enhanced Raman Spectroscopy (SERS) and Surface Enhanced Fluoresence (SEF) for rhodamine B (RhB) molecules adsorbed on gold nanoparticles was reported. By changing the deposition time, porous Au nanoparticle films with various densities and sizes were deposited. Via thermal annealing, the densities and sizes were modified. It is concluded from the results that the intensity of SERS and SEF varied in parallel with different Au nanoparticle films: different sizes and different densities. We believe that the results obtained can provide us with a reference when developing bio-chemical sensors based on Surface Enhanced Raman Spectroscopy and Surface Enhanced Fluorescence