“Pressure is the soul of the gas reservoir development.” Getting the accurate single well pressure is crucial to well proration and establishing the reasonable production system. For low permeability gas reservoir, the formation pressure recovery is so slow that the downhole static pressure getting from a short time shut-in varies greatly with the real average formation pressure. Thus, long time shut-in is required to obtain stability of the static pressure. In order to ensure the production task and reducing the workload of data monitoring, the article gives a bottom hole pressure correction method based on the principle of formation pressure transmission in seepage flow mechanics and pressure build-up testing data. This method makes the static pressure in different time is close to the current average formation pressure and provides the production site with fast and accurate method to estimate average formation pressure. At the same time, the pressure correction can be used in other method of formation pressure like wellhead pressure conversion method and pressure drop method to get more accurate and reliable single well formation pressure.