Aims: Phlomis cancellata is an aromatic and native plant that is a member of Labiatae. Not only a traditional medicine but also the plant is considered in modern medicine and different industries because of it s essential oil characteristics. The features of essential oils in aromatic plants are based on the part of plant from which they are extracted. In the present study the chemical composition of the essential oils of different parts of the Phlomis cancellat a were evaluated. Place and Duration of Study: Plant was collected from its natural habitat in Mazandaran province, Iran, in July 2012, its parts were separated and then dried in laboratory (Nour Branch, Islamic Azad University, Iran) and essential oils were extracted by hydrodistillation. Methodology: The essential oil of P. cancellata obtained by hydrodistillation and analyzed by GC FID and GC/MS. Results: The chemical analysis has resulted in identification of 25, 20, 11 and 2 constituents,