Abstract: Natural remedies, such as those based on traditional Chinese medicines, have become more popular also in westerncountries over the last 10 years. The composition of these herbal products is largely unknown and difficult to determine.Moreover, since plants respond to their environment changing the metabolome, the composition of plant material can varydepending on the plant growth conditions.However, there is a growing need of a deeper knowledge on such natural remedies also in view of the growing number of reports oftoxicity following the consumption of herbal supplements. Untargeted metabolomics is a useful approach for the simultaneousanalysis of many compounds in herbal products. In particular, liquid chromatography/mass spectrometry (LC-MS) can determinepresence, amount and sometime structures of plant metabolites in complex herbal mixtures, with significant advantages overtechniques such as nuclear magnetic resonance (NMR) spectroscopy and gas chromatography/mass spectrometry (GC-MS).