For exploratory wells where natural gas has been discovered in new regions or for new adjustment wells in mature areas，it is essential to conduct productivity testing （also known as deliverability testing） after completing the gas test and shut-in to obtain the reservoir pressure， to determine the absolute open flow rate and inflow performance relationship （IPR） curves of the gas well.These results provide a reliable technical foundation for developing the gas reservoir development program. Internationally， methods for evaluating gas well productivity are mainly quadratic form and exponential form expressed by the squared pressure and solved by the production of the gas well and the corresponding flowing bottomhole pressure from a multi-point test （typically four points）. In this paper， the productivity equation for the pseudo-pressure of the gas well was derived based on the quadratic equation for the pressure gradient and flow velocity proposed by Forchheimer （1901） and the pseudo-pressure function proposed by Al-Hussainy （1966）. Additionally， the exponential equation of pseudo-pressure was obtained by using the correction method proposed by Rawlins （1936）. Example applications demonstrate that the evaluation results for absolute open flow rate are essentially identical using both the quadratic and exponential equations expressed in terms of pseudo-pressure.