Functional and nutritional compounds have been increased during the germination of the brown foxtail millet. However， the characteristic smell is also produced， and affects the quality of the germinated brown foxtail millet. To control and improve the quality of the germinated brown foxtail millet， the origins of the volatiles must be known. Two cultivars of the brown foxtail millet， Jigu 39 and Jichuang 1， were used for 24 h germination. The volatiles were detected using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that 5 aldehydes， 2 ketones， and 2 esters were mainly produced after 12 h germination， whereas 10 alkanes and 4 alkenes were mainly produced at 0-12 h germination of the brown foxtail millet. The volatiles were mainly produced by the enzymatic oxidation of the fatty acids. The palmitic acid， stearic acid， oleic acid， linoleic acid， and linolenic acid were increased first and then decreased. The model experiment showed that the nonanal and decanal were enzymically formed by oleic acid， 3-octen-2-one and (E)-2-octenal were enzymically formed by linoleic acid， and dodecane and nonanal were enzymatically formed by linolenic acid.