Abstract: In this study, a new type of material ( MonoTrap) was applied as the adsorbent for headspace sampling to extract the volatile compounds in the meat of steamed Chinese mitten crab ( Eriocheir sinensis) farmed in three different regions.The volatile compounds were then isolated and identified by GC- MS and a total of 81 volatile compounds were finally detected. Based on the odor threshold, 19 key aroma compounds whose ROAV values greater than 1 were further selected and their formation mechanism were also discussed in detail.Among the 19 key aroma compounds, 3- methyl- butanal, 2- methyl- butanal, hexanal, heptanal, 4- heptenal, benzaldehyde, octanal, nonanal, decanal, 2-ethyl-furan, 2-pentyl-furan, trimethylamine, 3-ethyl-2, 5-dimethyl-pyrazine and 1-octen-3- ol were found in the meat of Eriocheir sinensis farmed in all three regions, while 2- butenal, 1- penten- 3- one, 2-decanone and 2-pentyl-pyridine were only found in the meat of Eriocheir sinensis farmed in Chongming region.