Abstract: A high power 25/400 m ytterbium doped double-cladding fiber(YDF) with excellent beam quality was successfully fabricated by MCVD in conjunction with solution doping technology. The dopants of the silica fiber core include Yb2O3, Al2O3 and P2O5. Al2O3 could reduce the clustering of Yb3+ and increase the doping concentration. P2O5 was helpful to restrain photodarkening phenomenon. The core-cladding refractive index difference is 0.001 2, corresponding to the core numerical aperture of 0.06. The value of the cladding absorption is 2.1 dB/m at 976 nm. Master oscillator power amplifier configuration based on two end pump was constructed to test the Yb-doped fiber performance. In the experiment, the power of the 1 080 nm seed is 235 W, the total power of the pump power is 3 706 W. The maximum output power is 3 243 W with a slope efficiency of 81.1%. The beam quality factor was measured to be 1.7. Stimulated Raman scattering(SRS) has not been found in the output laser spectrum. The fiber laser continues to work for one hour, the output power is stable at 3 240 W. In addition, a kind of 25/400 m imported fiber was tested in the same experiment schematic. Comparative experimental results show that the performance of the domestic fiber is close to the imported fiber.