Simplified load spectrum is an effective method for shortening the time of fatigue test. A simplified load spectrum method is put forward with the advantages of three-parameter S-N curve of whole life adaptability, the simplicity and precision of DFR method and the invaria nce of the total damage of equal damage reduced method. Reduced load is determi ned by setting the ratio of damage thresholdγac according to the ratio of d a mage between a certain load level and the maximum load level cycle time(γ). Conside ring spectral model for fatigue test, spectrum shape factor is introduced to re duce the effect on fatigue damage and dispersion fatigue life by changing the ty pe of load spectrum. A set of simplified load spectrum method is formed combine d with the handling of small loads under fatigue limit. Experiments prove that the d amage of simplified load spectrum is close to the damage of original load spect rum, but the test time is greatly decreased. The validity and engineering usabi lity of the load spectrum simplified method based on the DFR method with t hree-parameter S-N curve is well proved.