The influence of gold nanoparticles on the optical properties of dye molecules of Rhodamine 6G (R6G) and fluorescein (FL) has been studied. The adsorption of positively charged R6G on the surface of gold nanoparticles passivated with citrate resulted in a red-shift of the surface plasmon resonance (SPR) of the gold nanoparticles. Negatively charged FL, on the other hand, had slight influence on the SPR of the gold nanoparticles, likely due to the electrostatic repulsion between FL and citrates. The surface-enhanced Raman spectrum of R6G on the gold nanoparticles demonstrated that R6G adapted a parallel orientation relative to the surface of the gold nanoparticles. The nonradiative energy decay and unfavorable orientation of R6G to gold nanoparticles led to a decrease in the intensity of the emission of R6G. In contrary, the emission intensity of FL was substantially increased in the presence of the gold nanoparticles, due to the necessary space generated by the electrostatic repulsion between FL molecules and the citrate-passivated gold nanoparticles.