Load spectrum obtained from automobile proving ground contains a large number of high frequency low amplitude loads,so the key step of establishing four-column bench test of a vehicle is to conduct the acceleration processing of measured load spectrum. Based on the measured load spectrum of a certain car ’s proving ground,combined with fatigue cumulative damage rule and low-load strengthening theory,a new principle that named low-load deletion was put forward. With the application of this principle in editing measured load spectrum, the accelerated test spectrum could be generated. The effectiveness of accelerated spectrum was theoretically verified from amplitude domain,pseudo damage and frequency domain.The results showed that,on the basis of retaining damage,together with ensuring the damage of load features and domain features,this method had achieved the acceleration. Finally,in the process of establishing vehicle bench test,the failure mode was consistent with that existed in automobile proving ground,so the rationality of load spectrum’s speedup method was verified.The method could provide a reference for accelerating the draw up of other models’ four-column bench test load spectrum.