Based on the experimental researches on the fluorescence spectra of 1% erythrocyte solution with various concentration of alcohol excited by violet light-emitting diode LED light at 407 nm, the mechanism of alcohol on the fluorescence spectra of erythrocyte solution is investigated theoretically. The experiment results indicate that induced by the LED light at 407 nm, erythrocyte solution with the concentration of 1% can emitting striking spectra with two fluorescence regions. One is the short-wave fluorescence region from 430 to 525 nm, and the other is the long-wave fluorescence region from 580 to 750 nm. When the concentration of alcohol in erythrocyte solution increasing, the fluorescence intensity of short-wave area decrease while the fluorescence intensity of long-wave area increases. Combining the blood absorb spectra to the experiment results, it is shown that the formation of the short-wave fluorescence area is because the solution transmits the fluorescence spectra and the self-absorption of erythrocyte. The long-wave fluorescence region comes from porphyrin such as protoporphyrin, zinc porphyrin etc.. And there is resonance energy transmission between the short-wave fluorophores and the long-wave ones. According to the experiment results and the physical theory in erythrocyte fluorescence, it is found that alcohol make higher self-absorption ratio of the erythrocyte which improves the resonance energy transmission between fluorophores in the two wave bands. The result will offer experimental and theoretical reference for examining the alcohol content in blood.