Bergenia crassifolia L., Saxifragaceae, is an evergreen perennial plant known in traditional medicine of Russia, Mongolia and China. Polyphenols are responsible for the number of pharmacological effects of Bergenia. UPLC-DAD-QqQ-MS and LC-DAD-ESI-QTOF-MS were used for the rapid profiling of phenolic compounds, mainly hydrolysable tannins. Green leaves consisted of 55% ellagitannins, 29% gallic acid derivatives and 11% flavonoids, with the remaining gallic acid, arbutin, bergenin and caffeoyl quinic acid. In fermented leaves, 31% of gallic acid was found, followed with 28% ellagitannins, 18% gallic acid derivatives and 18% flavonoids, with the remaining caffeoyl quinic acid, bergenin and arbutin. Tellimagrandin I, pedunculagin, caffeoyl quinic acid, monogalloyl quinic acid, 1-O-galloylglucose and 1,2,6-tri-O-galloylglucose were identified for the very first time.