Copper content in the hepatopancreas of wild parentPanaeus orientalis was more than 500 μg/g (wet wt), among which over 90% distributed in the cytosol. 99% of the Cu in the subcellular fraction distributed in a very low molecular weight (VLMW)pool.DE-11 anion exchange chromatography of the VLMW material indicated that about 83% of the Cu in the pool could not be absorbed in the exchanger. Some main compounds containing copper (accounting for 77% of the Cu in the cytosol) were isolated from the cytosol fraction using a CM-32 cation exchange column. Amino acid analysis of the compounds showed that histidine was a major component, accounting for 58.2% of the total amino acids in the compounds, and that the contents of lysine and serine were also higher (9.6% and 7.6%, respectively), indicating that Cu in the material isolated by CM-32 perhaps mainly existed as a histidine-Cu complex, and that some of it could have complexed with serine, glysine and/or their peptides.