Tight reservoir has poor porosity and permeability, so it is necessary to use volume fracturing in horizontal wells to increase seepage area and communicate natural fractures, so as to realize high efficiency production. In order to comprehensively analyze influence factors of fracture network, and provide scientific geological model for the next production forecast, the method system of key parameters of natural fracture and fracture network is established, design the simulation model, which including the formation of the geological model, natural fracture simulation and fracture network simulation integrated software the 3 part, analyzes the influence of brittleness coefficient, horizontal stress difference, natural fracture, net pressure changes caused by fracturing fluid displacement and fracturing fluid volume parameters on fracture network size and communication. In depth analysis of these factors can provide reference for the field.