Abstract:To determine the flavor characteristics of the chlorella growth factor，this paper compared the extractic effect of volatile flavor substances by headspace-solid phase microextraction（HS-SPME）and solventassisted flavor evaporation（SAFE），Gas chromatography-mass spectrometry（GC-MS）were used to identify volatile flavor substances in the chlorella growth factor liquid.Based on this，this paper utilized gas chromatography-olfactory-mass spectrometry（GC-O-MS）and relative odor activity value（ROAV）to study the key volatile flavor substances in the chlorella growth factor.The results showed that，compared with SAFE，HS-SPME extracted more kinds of volatile flavor substances and their relative contents were higher. Besides，50 types of composition were identified，including alcohols，ketones，heterocycles，and aldehydes；5 kinds of key flavor substances were selected through GC-O-MS and ROAV，which were 2-heptanone，2，4，5-trimethyloxazole，thiazole，dimethyl disulfide and 2-ethylhexanol. The result of this study provides a reference for the flavor formation mechanism of chlorella growth factors and the development of chlorella food.