Abstract: This study is focused on commingled production from multilayer gas reservoir for effective analyses of the production feature and dynamic reserves of each gas layers. A commingled production model of multilayer reservoir is constructed through a parallel connection of core sets with different physical properties. The established model, which provides a means for researching the production mechanism and dynamics of multilayer commingled reservoir, is then used for assessing the effects of reservoir physical properties, pressure difference, and production proration on commingled production of multilayer gas reservoir. Experimental results show that the variations in the contribution of each sub-layer to total gas production increase with the interlayer differences of physical core properties as well as the production proration. Among different sub-layers, high-permeability layer makes greater contribution to gas production in an early stage, whereas low-permeability layer makes an increasing contribution to gas production over time with the major contribution in a late stage. Backflow from high- to low-pressure layer easily occurs in commingled production of multilayers with different pressures. Therefore, when interlayer pressure difference is formed in commingled production of multilayer gas reservoir due to the difference of physical reservoir properties, well shut-in should be avoided for preventing interlayer pressure fluctuations and related reservoir damage.