Non-premixed combustion flow with C16H29 fuel in gas turbine combustor was simulated by commercial software fluent. Under a design condition, the turbulence was solved by the RNG k - epsiv two-equation model, the physical nozzle was simulated by the discrete phase model (DPM) and discrete random walk (DRW) model, the reaction and NOx exhaust were analyzed by different reaction models as eddy dissipation concept (EDC)-2Step model, EDC-5Step model and thermal & prompt NOx models respectively. The result shows that there is a lower peak temperature, a better uniformity of temperature in outlet as 28%, a lower NOx exhaust as 728 ppm with EDC-5Step model including exothermic reactions.