Abstract: In order to investigate the refining effect and difference of different refining components of natural flavor from Siraitia grosvenorii by membrane separation technology, a Siraitia grosvenorii extract was prepared with a 50 nm ceramic membrane and a 100 kDa organic membrane. The Siraitia grosvenorii extract was divided into four fractions, labelled as M1, M2, M3, and M4. The volatile components in each fraction were analyzed by GC-MS and followed by principal component analysis. In addition cigarette flavoring test was conducted. The results showed that:1) Sensory evaluation indicated that M3 was the best flavoring fraction. 2) There were 43 components detected in the four fractions, in which 24 components were detected in M3 fraction with the total material amount of 2 585.41 μg/g. Among the flavoring components, farnesol and cis-β-farnesene could provide floral, green and woody aroma to cigarette. 3) Principal component analysis suggested that M3 significantly differed from M1, M2 and M4, however there was no significant difference between the flavor components of M2 and M4. The main components in M3 were hexacosane, tricosane, α-farnesene, (E,E)-3,7,11-trimethyl-2,6,10-dodecatrienal, S-(Z)-3,7,11-trimethyl-1,6,10-dodecatrien-3-ol, heneicosane, oleic amide, etc. 4) The volatile component analysis of particulate matters showed that M3 could also reduce the release of alkanes and benzene-based substances (regardless of the type or content) in particulate matters of cigarette smoke and might have a positive impact on reducing some toxicants.