Soot volume fraction and number density in a turbulent diffusion flame burning kerosene/air were predicted using two approaches. The first used a conventional soot inception model based on the acetylene concentration and is referred to as the acetylene model. The second used a soot inception model based on the formation rate of three and two ring aromatics [1] and is referred to as the PAH inception model. The soot models account for inception, coagulation, surface growth, and oxidation processes. The Favre-averaged governing equations of mass, momentum, and energy in the turbulent field were solved in conjunction with the k turbulence model. A recently developed detailed reaction mechanism for kerosene/air [2] was coupled to the turbulent flow field by the stretched laminar flamelet approach. A radiation heat transfer model that considered the soot, water and CO2 levels is included. Models are validated by comparing the numerical results to the experimental results of Young et al. [3] for a turbulent jet-flame burning pre-vaporized aviation kerosene. Significant improvements in the prediction of soot volume fraction are obtained using the PAH inception model for soot inception compared to the conventional acetylene approach. © 2003 The Combustion Institute. All rights reserved.