The production decline model is of vital importance to predicting the production rates and recoverable reserves of oil-gas wells and reservoirs. Its effective application is not limited by the ways it is reserved，driven，fractured，and recovered as well as the fluid in it.In the decline stage of production rates，the production rates and recoverable reserves can be predicted with enough production data. After years of application，Arps，in 1945，created the exponential decline model，the harmonic decline model，and，more importantly，the representative hyperbolic decline model. Moreover，the pan exponential decline model is practically valuable. Theoretically，the decline exponent n of the hyperbolic decline model ranges from 0 to 1 and the model is practical when n falls between 0 and 0.5. However，the pan exponent m of the pan exponential decline model can be valued at，in theory，between 0 and 1. The model is feasible when m ranges from 0.5 to 1. For n=0 or m=1 of the corresponding models，the exponential decline model can be obtained. For both n=0.5 and m=0.5，practical models can be built. The formulas of production rates，cumulative productions，recoverable reserves，decline rates，dimensionless production rates，and dimensionless cumulative productions of shale gas wells and tight gas wells，and dimensionless cumulative productions are proposed. According to application cases，the two models made similar predictions.