Numerous in vivo impacts tests have been conducted on animal heads for the investigation of the traumatic brain injuries results from real-world impact accidents.The mass-based scaling law has long been used as a principal method for the scaling of input loadings as well injury thresholds between surrogate animal brains and human brain in those animal impact tests.The purpose of this study was to evaluate the performance of the mass-based scaling law for brain injury criteria.Coronal plane rotational impacts were simulated using a rat head FE model and a human head FE model.Amplitudes and durations of rotational accelerations were defined based on prior in vivo experimental tests on rats.In total, 18 simulations, including 9 simulations using the rat brain model and 9 simulations using the human brain model,were conducted.Strain responses were extracted from four anatomical regions of interest (ROIs): parietal cortex,hippocampus, thalamus, and hypothalamus.From the comparisons of peak strains of those ROIs, different strain patterns could be observed between those two head FE models.Meanwhile, the effects of the rotational acceleration durations on the peak strains of those ROIs were weaker in the human head FE model than the corresponding effects in the rat head FE model.Similar effects of the rotational acceleration amplitudes on the peak strains of those ROIs were observed between those two head FE models.The simulations demonstrated that, the mass-based scaling law could be used for the scaling of the amplitude of inputted rotational accelerations, but it has limits for the scaling of the acceleration durations.Moreover, region-specific characteristics should be considered in scaling procedures of brain injuries between animals and human.