Background and objectives: Ornithogalum procerum Stapf. (Family: Liliaceae) is an Iranian medicinal plant found mainly in the east Azarbaiijan province of Iran. As part of our ongoing phytochemical and bioactivity studies on medicinal plants from Iranian flora, various extracts and essential oils of this plant were analysed by GC-MS.Methods: The hydrodistillation of the ground aerial parts of O. procerum, Soxhletextraction of the dried and ground bulbs, and the hydrolysis of the methanol extract of the bulbs yielded, the essential oils, n-hexane extrcat and the hydrolysed methanolic extract respectively, which were analysed by the GC-MS.Results: A total of 23 compounds were identified from the essential oils of the the aerial parts. The identified compounds represented 70.27% of the total essential oils. The main components of the aerial parts were phenylacetaldehyde (7.57%), hexahydrofarnesyl acetone (8.13%), docosan (5.52%) and 5-methyl octadecane (4.63%). From the n-hexan extract of the bulbs, seven hydrocarbons representing 99.39% of the total extract, were identified. Finally, from the hydrolyzed methanolic extract of the bulbs, four polysteroltype compounds accounting for 59.81% of the extract, were detected.Conclusion: The GC-MS analyses reavealed that the essential oils are mainly composed of oxygenated hydrocarbons, the n-hexane extract contains predominatly hydrocarbons, and the hydrolyzed methanolic extract comprises polysterol-type compounds.