Abstract: The total and free fatty acid compositions and contents of four different parts in male and female Chinese mitten crab were analyzed by gas chromatography ( GC) .The results showed that: in total fatty acids, there were more kinds of total fatty acids in female abdominal meat and claw meat and crab paste.The contents of total fatty acids in crab spawn and crab paste were higher than crab meat.The percentage compositions of C16∶0, C17∶0, C18∶0 and C23 ∶ 0 were higher in SFA, C18 ∶ 1n9c, C16 ∶ 1n7, C20 ∶ 1n9 and C22 ∶ 1n9 were higher in MUFA, and C18∶2n6, EPA and C22∶6ns were higher in PUFA.In free fatty acids, the contents of C17∶0, C15∶0, C18∶0, C22∶1n9, C18∶1n9c, C18∶2n6c, C20∶5n3 and C22∶6ns were higher.Moreover, through the cluster analysis, the compositions of total and free fatty acids of crab meat were similar.The compositions of total fatty acids of crab spawn and paste were similar, but the free fatty acids compositions were different.