Silver catalyst-mediated Gallium Nitride Nanowires (Ag-GNNWs) were synthesized on Si (100) substrate taking Ga2O3 powder, N2 and H2 gas as raw material using a chemical vapor deposition (CVD) reactor. The structural, chemical network and optoelectronic environment of Ag-GNNWs were investigated by employing AFM, FTIR, Raman, XRD, Photoluminescence (PL), and XPS characterization with the variation of H2 flow rate. The AFM and XRD results confirmed that the diameters and crystallite size, D of Ag-GNNWs varied from 50 to 250 nm and 15.06 nm respectively. The microstrain of Ag-GNNWs varied from 0.00174 to 0.01183 with an increase of H2 gas reduced atmosphere. The FTIR signatures at 463, 514, 567, 610, 667 and 739 cm−1 correspond to H-Ga-O, N-Ga-N, N-Ga-O, O-Ga-O(GaOO), O-Ga = O(O-Ga = O) and A1(LO) phonon respectively indicated Oxygen present as contamination. The increase in FWHM of Raman spectra signified decreased phonon lifetime of the transverse optic (A1 & E1), surface optic (A & E), E2(High) and defect-induced phonon with increasing H2 gas flow rate. The ISO(A) / ISO(E) and its respective FWHM ratio increased from 1.22 to 1.49 and 1.09 to 1.30 cm−1, indicating decreasing structural anisotropy and crystalline quality with the variation of H2 flow rate. The prominent PL peak centered at around 2.97 eV implied nitrogen-vacancy (VN) in the Ag-GNNWs. The XPS spectrum confirmed the presence of Ga, Ag, N2 and O are present in Ag-GNNWs. Moreover, semiempirical deconvolution predicts possible chemical networks in the Ag-GNNWs.