针对低渗透油田五点法注水开发井网，采用数值模拟方法，研究了整体压裂改造中水力裂缝方位及参数对采收率的影响。提出了把油藏与裂缝按一个系统建立数学模型的求解方法，并通过实例计算和文献结果对比，验证了这种方法的可行性。 Aiming at the well pattern of five-point waterflooding in low-permeability oilfield, numerical simulation method was used to study the influence of hydraulic fractures orientation and parameters on oil recovery in the whole fracturing reformation. The solution to the mathematical model of reservoirs and fractures is put forward according to a system. The feasibility of this method is verified by comparing the calculation results with the literature results.