Background: Micromeria fruticosa (L.) Druce ssp. brachycalyx P. H. Davis and Rhus coriaria L., which are Lamiaceae species, are used both as spices in food and medicinally. Lamiaceae species are known to contain high amounts of polyphenols. In this study, liquid chromatography-quadrupole time-of-flight-tandem mass spectrometry (LC-QTOF-MS/MS) was used for analysis of polyphenols in the plants. Under gradient elution with using 0.1% aqueous acetic acid solution and acetonitrile mobile phases, an Agilent Poroshell C18 reversed phase column was used for the simultaneous determination of 18 polyphenols, and separation was performed in 30 min. Pharmacokinetic properties of these polyphenols such as drug-like and toxicity were estimated using open-source software, pkCSM and SwissADME.