Extraction of geothermal energy, oil and gas, and coalbed methane (CBM) are all constrained by the rock's permeability. To stimulate the production, hydraulic fracturing has become a routine procedure, which is influenced by many factors especially the pre-existing natural fractures. The natural fractures have various characteristics, such as aperture, persistence, and density, which have different effects on the hydraulic performance. Hence, it is necessary to study the dependence of hydraulic fracturing on natural fracture parameters to improve its effectiveness. In this research, the distribution of natural fracture is generated using the discrete fracture network (DFN) to study these relationships. To verify the accuracy, the numerical model is calibrated at a particular case with observed data and then continued to different fragmentation characteristics. Results show that the hydraulically fractured area has an inverse relationship with the natural fracture aperture. However, the increase of pre-existing fracture persistence first causes the fractured zone to increase but increasing persistence of natural fractures further causes the area to decrease. Parametric study shows that pre-existing natural fractures play a critical role in hydraulic fracturing effectiveness, which ultimately affects the production.