Abstract: In this research was the study of the phenomenon of fluorescence energy transfer between two laser dyes. One models have been prepared in this study, the acceptor dye (acridine orange) with the donor dye (rhodamine B). The absorption spectra and the emission spectra of the acridine orange and rhodamine B dyes were studied with different concentrations (1×10-3, 1×10-4, 1×10-5) mL in ethanol solvent. The results of the study showed a significant increase in the intensity of the fluorescence spectra of the mixing samples compared to the dyes individually for all the prepared samples. We note change all the linear optical properties (absorption coefficient, refraction index, quantum yield, lifetime of the energy level of fluorescence) of (acceptor+donor ) samples prepared compared to what it was before mixing.