Low permeability reservoir has a lower permeability, hydraulic fracturing is often used to improve the productivity of the well. The evaluation of the productivity of fracturing well is essential to the development of the low permeability reservoir. On the basis of a new model which describes the low-velocity nonlinear seepage law, the formulas are established for the vertical fractured wells with both infinite and finite conductivity. A comparison and analysis are made on productivity between Darcy's model and start-up pressure gradient model. The results show that there are some differences on productivity only under very low production pressure dif-ference, and with the pressure difference increasing, and the fracturing well productivity predicted by three models becomes almost same. The productivity of fracture with finite conductivity that is equivalent to the vertical well productivity makes it easy for engineer-ing practice. Results show that the equivalent vertical well radius increases with dimensionless conductivity increasing and decreasing of dimensionless oil drainage radius.%低渗透储层往往通过水力压裂提高单井产能,垂直压裂井产能的评价对低渗透油田开发尤为重要.基于低速非线性渗流新模型,建立了低渗透无限导流能力和有限导流能力垂直压裂井产能公式,并与基于达西模型和拟启动压力梯度模型的垂直压裂井产能模型进行了对比分析.结果表明:3个模型所预测的产能仅在驱替压差非常小时有区别,其中达西模型预测的产能最高,低速非线性渗流新模型次之,拟启动压力梯度模型最小；随着驱替压力的增大,3个模型预测的产能几乎一样.为了便于工程应用,用等效直井产能表示有限导流能力裂缝的产能,结果表明,等效直井井径随无因次裂缝导流能力的增大而增大,随无因次泄油半径的增大而减小.
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