The Q-branch line widths of oxygen were measured by using high resolution coherent anti-Stokes Raman spectroscopy. The first nine transitions (N = 1–17) were recorded at pressures from 0.094 to 1 atm (1 atm = 101 kPa) at room temperature. The transitions were excited by injection-locked flashlamp-pumped dye lasers of very high spectral quality. A least squares program was employed to fit calculated spectra to experimental spectra by adjusting different parameters. The collisional broadening coefficients obtained were consistent with available Raman data.