These days, hydraulic fracturing is widely applied in the gas reservoir development with low permeability, which can improve the production of the well and enhance the recovery. This paper discussed the productivity characteristics of multiple-fractured horizontal wells (MFHWs) with three to five fractures by the use of the basic theory of potential. First, the seepage model of fractured horizontal wells with infinite inflow fractures and the stable and unstable seepage models within the fractures are analyzed. Second, the distribution of potential and pressure was quantitatively simulated for a given gas reservoir (mainly 3–5 fractures), and the potential and pressure at any point were derived. Finally, the fracture parameters of the MFHWs were optimized in terms of two evaluation indexes, the average fracture production and the single well production by the use of an orthogonal test. The optimized fracture spacing is 100–150 m, and the longer the fracture width and fracture length, the better production performance. The research results have theoretical significance and provide reference for the selection of fracture parameters for horizontal wells in low-permeability gas reservoirs and the productivity evaluation of MFHWs.