New experimental results were obtained to better assess the effect of ozone on the burning velocity of premixed methane air flames at atmospheric pressure and room temperature. Ozone was produced using a dielectric barrier discharge device, and its quantity was fixed equal to 5 g/Nm(3) in air (2369 ppm of ozone). Measurements were performed using a Bunsen burner. Simultaneous to flame height measurements, a ID Rayleigh scattering system was set up to investigate the impact of ozone on the thermal flame structure. The experimental results showed that the partial conversion of molecular oxygen into ozone has a moderate positive effect on the burning velocity of methane-air flames, confirming previous measurements in the literature. The injection of 5 g/Nm(3) of ozone in air increased the burning velocities by ca. 0.8-1.3 cm/s (ca. 3-8%). The oxidation of methane in the presence or absence of ozone was modeled using a detailed chemical kinetic scheme taken from the literature, to which an ozone submechanism was added. The computations agreed well with the present set of experimental data and represented the trends previously reported in the literature. Kinetic modeling was used to rationalize the present results and predicts increasing burning velocities with increasing air ozonization.