Abstract: To investigate the changes of odorants in samples of Chinese Mitten Crab( Eriocheir sinensis) at different arachidonic acid( ARA) level,the whole odor of these different samples were analyzed by E- Nose,then the types and concentrations of volatile compounds were compared by monolithic material sorptive extraction combined with gas chromatography- mass spectrometer.The discrimination indexes of gonad,hepatopancreas and muscle group from Principal Component Analysis( PCA) polt by E- Nose were 74,61,65,respectively,which illustrated that the whole flavor of samples were different significantly,and the most intensive sample was gonad group. Totally 67 volatile compounds which could be divided into 7 categories were detected from the three edible parts,and the largest contribution category was aldehydes. MMSE- GC- MS showed no difference in the types of volatile compounds in each part,while significant differences were found due to the diverse concentration of every odor compound by the different ARA levels,especially in gonad and hepatopancreas.The volatile odor profile of gonad and hepatopancreas was influenced by the different ARA levels in diet significantly,especially aldehydes,while muscle almost has no significant difference.