The effect of feeding and starvation on growth, gross biochemical composition and fatty acid composition of body, muscle and hepatopancreas were investigated in juvenile Chinese mitten-handed crab ( Eriocheir sinensis). The growth, biochemical composition, and relative composition of fatty acids were influenced by starvation. During starvation, body fat, especially hepatopancreatic neutral lipid content, decreased significantly ( p < 0.01). In hepatopancreas, there were marked relative decreases of 14:0, 16:0, 16:1 n − 7 and 18:1 n − 9 fatty acids and relative increases of 18:2 n − 6, 18:3 n − 3, 20:5 n − 3 and 22:6 n − 3 when these were compared with the controls during starvation prolonged 70 days ( p < 0.01). Meanwhile, in muscle 14:0 and 16:0 saturated fatty acids decreased remarkably and 18:2 n − 6 and 18:3 n − 3 polyunsaturated fatty acids increased significantly at the end of study (day 70) ( p < 0.01). Preference of utilization of fatty acids from hepatopancreas during starvation was as follows: 14:0 > 16:0 > 16:1 n − 7 > 18:1 n − 9 and conservation as follows: 18:3 n − 3 > 18:2 n − 6 > 22:6 n − 3 > 20:5 n − 3 > 20:4 n − 6, and 14:0 > 16:0 and 18:3 n − 3 > 18:2 n − 6 from muscle. The changes of fatty acids were smaller in muscle than in hepatopancreas. The experimental results also indicated the tolerance of juvenile Chinese mitten-handed crab to starvation was over 70 days.