Abstract: In October 2016, leaves were collected from 20-year Armeniaca sibirica in Chengde, Hebei province. Leaf oil was extracted by supercritical CO2 extraction technology, and analyzed by gas chromatography-mass spectrometry. 20 compounds were identified, including squalene, alkane, unsaturated fatty acids, esters, phytol, etc. Among them, squalene occupied 38.49% of essential leaf oil. Extraction technology of squalen was conducted by single factor and orthogonal design tests. The result demonstrated that the best technology was as follows: extraction solvent of petroleum ether (60-90℃), extraction temperature of 60℃, solid-liquid ratio of 1:10, and extraction duration of 2.5 hour, squalene content extraedted of 0.219%.