There is permeability anisotropy due to the high-permeability channels in extra-low permeability reservoirs，which leads to the different percolation behaviors between injectors and producers compared with conventional reservoirs，and different adaptability of well pattern infilling. Based on the percolation behaviors of anisotropic reservoirs and infilled well pattern，the calculation formula of plane percolation field between injectors and producers is obtained by using the superposition principle. The linear displacement is introduced to analyze the adaptability of infilled well pattern in the anisotropic reservoir. The driving pressure gradient is used to characterize percentage of producing reserve，and the dimensionless incremental percentage of producing reserve is proposed. A quantitative characterization method for producing reserve between injectors and producers is established. The results show that the initial inverted nine-point well patterns are systematically infilled to row well patterns to form linear displacement，which can effectively improve the producing reserve in the extra-low permeability anisotropic reservoirs. When the initial well spacing is greater than 400 m，the potential of producing reserve between injectors and producers is improved significantly.