The latest trend in aero engine industry is to reduce the emission levels to a maximum extent as well as to improve the combustion efficiency. One of the ways to reduce the emission levels and improve the combustion efficiency in gas turbine combustors is to operate with lean premixed conditions. However, design modifications are required in conventional combustors to operate at lean premixed conditions. A new combustor configuration was studied for lean premixed pre-vaporized (LPP) combustion. To arrive at LPP configuration a simple gas turbine Can-combustor geometry is modified by attaching a fuel air premixer chamber at upstream of the flame tube of basic diffusion combustor [1]. Reactive flow analysis was performed with both the LPP and conventional diffusion combustor using commercial CFD tool Fluent. Significant improvements were obtained from LPP combustor in terms of emission reduction. However, there are limitations for lean burning of fuel such as flashback and lean blow out. Present work is focused on studying these issues on the LPP combustor. These methodologies can be extended for other type of combustors after further studies.