Abstract The essential oils of Thymus pallescens de Noé and Origanum floribundum Munby leaves and flowers were analyzed by GC and GC/MS. The oil yields of T. pallescens were 2.8% for the leaves and 3.7% for the flowers, while those of O. floribundum were 2.0% for the leaves and 5.4% for the inflorescences. The major constituents of both the leaves and flowers of T. pallescens were p-cymene (17.4% and 9.2%), γ-terpinene (10.6% and 14.1%) and carvacrol (39.0% and 48.3%), respectively, while those of O. floribundum were p-cymene (22.3% and 9.6%), γ-terpinene (17.3% and 24.3%) and thymol (34.4% and 41.2%), respectively. For the both plants p-cymene and sesquiterpenes were essentially concentrated in leaves. Key Word Index: Thymus pallescens Origanum floribundum Lamiaceaeessential oil compositioncarvacrolp-cymeneγ-terpinene