The inner part of the oil pool flame could be divided into different combustion areas, and there have been a limited number of researches on the heat transfer characteristics within oil pool fire. Due to the lack of adequate researches on the characteristics of heat transfer in oil pool flame, this paper carries out an analytical study to pool flame spectrums of 92# gasoline, 95# gasoline and lube by establishing flame infrared testing system. Spectral information about different combustion regions of oil pool fire is collected. The results show that three kinds of oil pool fire have similar spectral characteristics, with several characteristics emission bands of such combustion products as CO2, H2O and carbon black particles and that 3.4 μm C—H stretching vibration peak is obvious; the main spectral characteristics of smoke zone is high temperature CO2 emission peak at the band range of 4～4.5μm, the heat exchange of flame and air is violent; the temperature changes unstably, and flame pulse frequency is high; spectral characteristics in the intermittent area is high temperature CO2 emission peak at 4～4.5 μm; and flame pulse frequency in intermittent zone is relatively lower compared with that in the smoke zone; compared with that in the flue gas zone and intermittent zone, the combustion in continuous zone is more stable, the spectral characteristics of the region is obvious, and carbon black particle emission intensity is high at 2.5～3 μm, and C—H stretching vibration emission peak shows itself at 3.4 μm, which showed that the characteristic peak oil pool flame spectrum at 3.4 μm is caused by high temperature oil vapor steam. Spectral characteristics analysis of the oil pool flame in different combustion areas shows that the heat transfer is absorbed by the fuel rich layer on the surface of the oil pool flame, which leads to the change in the energy level of the oil vapor near 3.4 μm. The calculation of the emission spectrum intensity of oil pool flame in different combustion areas shows that the intensity in flame continuous zone is the largest, followed by the intermittent zone, that the connection between the flame smoke zone and the air is strong, and that the emission spectrum intensity is the lowest. The results in this study provide a reference for the modification of flame oil heat transfer model.