The low permeability gas reservoir of Xujiahe Formation in central Sichuan is facing the situation of high water saturation, low single well productivity and difficulty in stabilizing production. It is urgent to optimize and adjust production plan to improve productivity. Therefore, the pore and permeability characteristics of different types of reservoirs are analyzed by CT scanning. Secondly, the gas-water two-phase and gas-phase single-phase percolation characteristics of different types of cores are experimented under formation conditions. The results show that the core type has a higher influence on permeability than porosity and pore throat radius; with the increase of water saturation, the gas flow ability decreases greatly; under the condition of irreducible water, the gas flow in porous cores has a starting pressure gradient, and when the production pressure difference is less than 16 MPa, the gas flow is in the same state. In the low-speed non-Darcy stage, the lower limit of permeability is 0.32mD under this differential pressure. In actual production process, gas well productivity can be improved by controlling water saturation, improving reservoir conductivity or increasing production pressure difference. This study has reference significance for grasping the gas flow characteristics of low permeability gas reservoirs and optimizing and adjusting production schemes.