To explore the effect of decocting time on the component transformation and anti-fatigue effect of Triphala decoction.HPLC method was used to track the changes of ingredients in Triphala decoction during decoction.Twelve differential compounds were screened through partial least squares discriminant analysis (PLS-DA) and seven of these were identified as gallic acid,chebulic acid,chebulinic acid,chebulagic acid,ethyl gallate,ellagic acid and corilagin.During the decoction,the contents of chebulinic acid,chebulagic acid,ethyl gallate and ellagic acid all decreased while the gallic acid and chebulic acid increased.Corilagin′s content increased first,then reduced.The anti-fatigue effect of Triphala decoction with different extraction times was then evaluated.The longer the decoction time,the more potent the anti-fatigue effect was,according to the results of swimming time and 11 fatigue-related markers in mice.Gallic acid and chebulic acid,among the differential compounds,have the greatest impact on the anti-fatigue effect.It demonstrates how decocting can encourage the hydrolysis of the macromolecular tannins in Triphala decoction into gallic acid and chebulic acid,which can improve the anti-fatigue effect of Triphala decoction.