When an oil field with low permeability oil reservoirs is developed with horizontal wells, hydraulic fracturing is usually necessary to achieve an economic oil production rate. It is necessary to find a method for predicting performance of fractured horizontal wells. A practical method to predict performance of a horizontal well which is hydraulically fractured and partially perforated has been proposed in this paper. Using the mathematical model presented in this paper, factors affecting performance of a hydraulically fractured horizontal well have been analyzed. Two oilfield cases from the Daqing Oilfield are analyzed using the method and presented in this paper. Calculations and analyses show that the results which are calculated using this method are consistent with the actual results from the oilfield.