Abstract: In order to study the refining effect of the membrane separation technology on the extract of the iris and the difference of different refining components, the extract of the iris root was separated by 50 nm ceramic membrane, and the iris was analyzed by gas chromatography-mass spectrometry (GC-MS). Root extract that permeated through the membrane component, and the volatile matter of the retentate that did not pass through the membrane, were subjected to principal component analysis. Finally the cigarette flavoring test was carried out. The results showed that: ①There were 81 components detected in the three fractions, in which 38 components were detected in Iris root extract with the total material amount of 173.01 μg/g. 46 volatile substances were detected in the permeation membrane fraction, the total amount was 89.74 μg/g; 43 volatile substances were detected in the non-permeation fraction the total amount was 90.14 μg /g; ②Principal component analysis showed that the three components are divided into three regions according to the distance, and the three components are far apart, indicating that the main components of the aroma components in the three components are different. ③Sensory evaluation showed that among the three components, the perfuming effect of the extract of the iris root was better.