Shale gas is one of the unconventional natural gas resources，and shale gas reservoir is composed of extra-dense matrix and natural fracture system. Shale gas in the matrix is adsorbed gas that is self-generated，self-stored and selftraped，while that in the fracture system is free gas. Overall adsorbed gas is the main resource of shale gas，which will be desorbed at the fracture surface created by multistage fracturing in the horizontal well. The desorbed gas and free gas controlled by the horizontal wells are generally called well-controlled movable gas in-place and recoverable reserves. Volumetric method is the most common one for estimating resources of adsorbed gas in the matrix and free gas in the fracture systems in the shale gas reservoirs. However，the application of the volumetric method is greatly influenced by the validity of data including original adsorbed gas content，effective porosity in the fracture system，shale bulk density，and initial formation pressure. It should be noted that the volumetric method formula is uncorrected which was reported in the 2014 national technical standards for shale gas resources/reserves estimation. Moreover，the standards do not refer to any specific content about performance estimating methods. Therefore，considering shale gas is developed in well unit，performance method was presented as to estimate the well-controlled movable in-place and recoverable reserves of shale gas wells. The results of actual application in 3 shale horizontal gas wells indicates that the new method is practical and effective.