Abstract: The lavender has been widely used in food, aromatherapy, fragrant and pharmaceutical industries due to its unique chemical composition which confers both aromatic and biological activities. A method was established to fast identify the chemical constituents by phase micro-extraction-gas chromatography-mass spectrometry (SPME-GC/MS) and provided the basis for distinction of the different species by analyzing the remarkably different chemical components in the lavender. Based on the peak areas of cis-β-ocimene, linalool, linalyl acetate, terpinen-4-ol, caryophyllene and caryophyllene oxide, three parameters (temperature, time of extraction and desorption time) of headspace solid-phase micro-extraction (HS-SPME) were optimized, resulting in the best extraction condition including extraction temperature of 55 ℃, extraction time of 30 min and desorption time of 30 s. Twenty-six volatile oil samples collected in Xinjiang which belong to three different lavender species were analyzed by GC/MS．Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were used to analyze the aroma profiles of the lavender. The results show that the chemical compositions in lavender from different species are clearly distinguished. Kinds of 9 chemical compositions, such as linalool, caryophyllene, cis-β-farnesene, linalyl acetate, lavandulyl acetate, germacrene D, cis-β-ocimene, terpinen-4-ol and caryophyllene oxide, which are indentified as discrimination markers. This study can provide the basis for rapidly qualitative analysis of constituents and quantity control of the lavender.