In this work, the evidence of SF6 gas decomposition at the vicinity of SiO2 glass has been investigated using various laser wavelengths: at 193, 248, 532 and 1064 nm. It was shown that SiF4 gas and S2F10 clusters were simultaneously created during ArF excimer laser irradiation, while no by-products were seen in the irradiation cell using Q-switched Nd:YAG laser. The gas content analysis was carried out using laser breakdown spectroscopy (LIBS) and Fourier transform IR spectroscopy (FTIR). Moreover, the fluorine penetration into the glass surface was studied by energy dispersive X-ray (EDX) microanalysis and wavelength dispersive X-ray (WDX) mapping to support the suggested mechanisms.