Abstract: The development of gasoline-air mixture explosion in a long-narrow confined space is closely related to the chemical kinetics. Therefore, an experiment on ignition characteristics of gasoline was conducted, and the appropriate chemical kinetic mechanism was selected according to the ignition delay time for simplification. Meanwhile, the elementary reaction with greatest effect on explosion ignition delay time was determined. On this basis, using PLIF(Planner Laser Induced Fluorescence technology), an experiment on characteristics of explosive combustion flow field of gasoline-air mixture in a long-narrow confined space was conducted, and the combustion process of gas mixture in flame during the explosion propagation was analyzed. In addition, numerical simulation on gasoline-air mixture explosion in a long-narrow confined space was performed by coupling the simplified chemical reaction mechanism with CFD. The results indicate that the large hydrocarbon molecules in the outer flame zone are thermally decomposed and dehydrogenated during explosion propagation. Meanwhile, oxidation reaction occurs and the generated free radicals expand to the inner flame zone, producing carbon granules and H₂O. Then, the carbon granules further react to generate the final products. Besides, the flame structure experiences several changes, and the disordered flame structure interacts with the increasing explosion overpressure to intensify the propagation of flame.In addition, the unburned gas flows forward at a decreasing speed, and the reverse flow occurs behind the flame front at an increasing speed. Then, the unburned gas at flame front close to the wall is burned, with the product flowing to the center of pipeline and the burned area. The gas mixture in the middle region is squeezed and moved to the burned area in the rear. The research results could provide theoretical guidance for the prevention and control of gasoline-air mixture explosion during petroleum production, storage and transportation.