Abstract: The computational method of oil well productivity calculated by using Block-oil model to stimulate hydraulic fracturing fractures is complex, so combined Black-oil model with fracturing design software is introduced to engage in productivity prediction in segregated fracturing horizontal. Firstly, segregated fracturing has been designed by fracturing software to stimulate hydraulic fracturing and obtain related parameters; secondly, the generated data file was input into Block-oil model, and reservoir matrix and fractures were finely meshed by model itself after preprocessing, during which fractures shape and flow properties in different condition could be captured exactly; thirdly, the inflow performance relationships of multi-phrase fluid from multi-layers to fracture and from fracture to wellbore were stimulated to analyze the influence of fracture geometry, conductivity capability, location, interval, included angle and matrix permeability on productivity. Taking flow back process of fracturing fluid into account, this method has provide important reference to predict oil well productivity in segregated fracturing horizontal wells.