Abstract: At present, it is difficult to develop the oil-water transition zones with low oil saturation by conventional means and it still has development potential by gas flooding and chemical flooding, but the development mechanism for the different types of oil-water transition zones is still not clear. Four natural core displacement experiments were carried out. Nuclear magnetic resonance(NMR) technique was used to study the starting mechanism and main distribution of residual oil in different types of oil-water transition zones. On this basis, the development characteristics of oil-water transition zone were studied. The experimental results show that gas flooding is more suitable for low permeability cores. The chemical flooding has a good producing degree for the residual oil in small pore because of the emulsification and the reduction of surface tension,which can obviously enhance oil recovery.