This study aims to investigate the impacts of premixed gasoline fuel on performance, emissions and combustion carateristics of diesel engine. A four cylinder diesel engine was used for experimental measurement of performance (torque, mean effective pressure, specific fuel consumption, brake thermal efficiency, etc), emission (NOx, CO₂, CO) and combustion (In-cylinder pressure, ignition delay, heat release rate, temperature) parameters. The engine was run at 1300 rpm with gasoline fumigation rate of about 20% of pure (commercial) diesel fuel at engine load of 25%, 50%, 75% and 100%. A computational fluid dynamics (CFD) model was developed using AVL Fire CHENKIN coupler software to predict performance, emission and combustion parameters, and chemical reactions. The model results were validated with experimental data and it was found that CFD model with chemical kinetics can reasonably predict the engine behavior during gasoline fumigation. For example, there was only 4.5% variation in mean effective pressure, 6% variation for emission, and 6.2% variation in In-cylinder pressure between the experimental measurement and numerical prediction. It was also found that the ignition delay of up to 2.85 ^oCA was more than commercial diesel. The model showed slight reduction in heat release rate and temperature during combustion. NOx reduces but CO₂ increases slightly. The detailed results will be presented and discussed in this paper.