Abstract:The gain character and power density distribution in the active fiber of double clad fiber laser (DCFL) with different pump modes are investigated by means of numerical analysis.It is demonstrated that by using two end pump mode the power density at the input parts of the fiber can be reduced obviously,and the uniformity of gain and power density in the fiber can be maintained simultaneously.The results show that two end pump is the optimum pump mode for high power DCFLs.