Effects of different water-borne copper（ Cu^2＋ ） （ 0.00, 0.01, 0.10, 1.00, 5.00 mg? L^-1 ） on distribution of copper in the body of Eriocheir sinensis and activities of some main digestive enzymes were studied by Single Gradient Factor Experiments. Among gill, epidermis and hepatopancreas of the animals in the control group without additive Cu^2＋ , average Cu^2＋ was 0.074, 0.036, 0.023 mg?g^-1 wet weight, respectively, which were determined by ICP-AES. When increasing of water-borne Cu^2＋ except for the hepatopancreas and epidermis in tested group with 0.01 mg?L^-1 water-borne Cu^2＋, Cu^2＋ level increased significantly （analyzed by SPSS software） in all organs studied and especially in the hepatopancreas. In the tested group in which water-borne Cu^2＋ was 5.00 mg?L^-1 Cu^2＋ level among the gill, epidermis, and hepatopancreas was 0.307, 0. 191, 0.341 mg?g^-1 wet weight, respectively. Furthermore, in the hepatopancreas the inhibition effect could be noted on activities of some important digestive enzymes, such as the typase, pepsin, amylase and cellulase in different extents during increase of water-borne Cu^2＋ . It is notable that such effect on the amylase was the most obvious even the level of additive Cu^2＋ was only 0.01mg?L^-1 that is the level of the National Water Purity Standard for Fisheries. Comparing with the control group, the activity of the amylase dropped sharply from 305.01 ? 32.23 to 36.81 ? 4.84 U?mg^-1. The maximum inhibition rate of this enzyme could be recorded as high as 89.96% in the tested group with 5.00 mg?L^-1 of water-borne Cu^2＋ . In contrast, the activity of the lipase enzyme was found increasing in all tested groups between 346.15% to 646.15%. The present study suggests that the different functional characteristics of the gill, epidermis and hepatopancreas may contribute to the change of Cu^2＋ distribution pattern among these organs for Eriocheir sinensis when the additive Cu^2＋ level in water was increased. Meanwhile, the hepatopancreas seems to be the main bioac Cu^2＋ mulation site, as well as the metabolic organ for Cu^2 ＋ . Moreover, the variations on the activity of the typase, pepsin, amylase and cellulase enzymes can sensitively indicate the inhibition effect of Cu^2＋ as well as its toxicity.