In the calculation of dynamic OGIP, the uptrend of dimensionless production indicative curve is not completely consistent with the nature of real water drive gas reservoirs.On the basis of the material balance theory combined with the aquifer model of Carter-Tracy and Schithuis, we compared the gas production with water or without water production, and analyzed the sensitivity of factors affecting production indicative curve of water drive gas reservoir.The production indicative curve of water drive gas reservoir is smoothly up convex on the whole.In the early stage, it takes the form of uptrend, straight or lower bending trend.The factors consist of aquifer volume, permeability of water bearing zone (water invasion index), compressibility coefficient of rock and formation water, formation depth and gas recovery rate.It was also proved by the depletion test with long core plug and the production practice of five real depleted water drive gas reservoirs that the conclusion is of guiding significance for actual development law.