The 532 nm laser ablation of Nb2O5 target in Ar and O-2/Ar ambient gas has been investigated using matrix isolation infrared spectroscopy. The major ablated products generated from Nb2O5 in pure Ar were found to be NbO+, NbO, NbO2, and NbO3-. With the addition of O-2 into ambient Ar, thr absorption intensities of NbO, NbO+ and NbO3- reduced apparently along with the significant growth of (O-2)NbO2 and a little increase of NbO2- in the IR spectra. The formation channels of these ablated products during the laser ablation process have been discussed both in pure Ar and O-2/Ar.