Blue laser has a wide range of application prospects in the fields of color laser display, highdensity optical storage, exploration of marine resource, underwater communication and biomedical sciences, etc. However, the relatively mature Yb3+ doped fiber laser can only obtain blue green (~490 nm) laser after frequency doubling. Therefore, it is an urgent issue to obtain a pure blue laser close to 450 nm. The 0.9 μm fluorescence generated by the 4F3/2→4I9/2 level transition of Nd3+ can obtain the pure blue laser output of ~450 nm after frequency doubling, which has excellent application potential in the field of blue laser. However, the fluorescence generated by this transition occupies a low fluorescence branching raito. In this paper, the absorption spectrum, fluorescence spectrum and fluorescence lifetime of 1% (mass fraction) Nd2O3 doped 50GeO2(20-x)PbO15BaO15ZnOxNb2O5 (x%=0%, 2.5%, 5%, 10%, 15%，mole fraction) glass were systematically studied, and the corresponding JuddOfelt intensity parameters and gain bandwidth were calculated. It is found that the 900 nm absorption cross section, emission cross section, effective linewidth and fluorescence branching ratio of Nd3+ increase with the doping of Nb2O5. When the concentration of Nb2O5 is 10% (mole fraction), JuddOfelt intensity parameter Ω2=5.91×10-20 cm2, the spectral quality parameter χ=1.01， and the fluorescence branching ratio is 42.9%. In summary, 0.9 μm fluorescence branching ratio of Nd3+ can be raised by Nb2O5, so as to obtain pure blue light (450 nm) by frequency doubling, which is beneficial to the development and application of blue laser.