The emission of fluorescence in the high-energy pulsed fiber laser will reduce pump efficiency when high energy pump power is injected into doped fiber.The emission mechanism of the fluorescence in high energy pulsed fiber laser was analyzed based on the level model of Er

3+

doped fiber(EDF).To explore fluorescence characteristic and improve the pump efficiency of high-energy pulsed fiber laser

a novel stimulation model is developed by combining the rate equation of Er

3+

doped fiber laser and nonlinear Schrdinger(NLS) equation.With the proposed mode and numerical method

we have made an investigation on the longitudinal propagation characteristics of pump light and fluorescence

and on the relationship among the fluorescence power

the pump efficiency and Er

3+

doping concentration.The numerical results show us that the pump and fluorescence power would decrease exponentially along the longitudinal axis of Er

3+

doped fiber and the fluorescence power decrease faster than that of the pump power.The fiber laser would emit less fluorescence when pumped by 980 nm laser than that pumped by 1480 nm laser.The results also show that when the pump power is certain

the power of fluorescence emitting in the EDFwould increase as the doped density does

and the pump efficiency would decrease as the doped density increase.When the attenuation coefficient is certain

the fluorescence power would attenuate faster when the gain coefficient increases.Comparing with the previous work

we found that the results given by the proposed model are in good agreement with experimental results in the references.Therefore

in order to effectively depress the fluorescence and improve the pump efficiency

pump laser with the center wavelength of 980nm is suggested to be chosen

and the doped density should be decreased as much as possible when the gain is certain

or the gain should be increased as much as possible when the doped density is certain.