Abstract: Nitrogen oxides emission from a series of turbulent methane jet non-premixed flames with different Reynolds number was numerically simulated, in order to investigate the influence of turbulence on the formation of nitrogen oxides.A two-scale k-ε turbulence model was adopted to calculate turbulent velocity field, and the probability density function (PDF) method was combined with the Lagrangian flamelet model to predict the turbulent scalar fields.Detailed chemical reaction mechanism GRI-Mech 3.0 was incorporated to describe methane oxidation and nitrogen oxides formation.The comparisons between nitrogen oxides predictions and measurements were made,and the influence of Reynolds number, scalar dissipation and flamelet time on the formation of nitrogen oxides was discussed. The numerical results were in good agreement with the measurements, and the trend that nitrogen oxides emission decreased with the increase of Reynolds number in the experiment was reasonably represented by the present numerical models.