Agrius convolvuli haemolymph ferritin was purified by KBr density gradientultracentrifugation and anion exchange column chromatography. The 670 kDa ferritin was composedof two subunits of 26 kDa and 31 kDa. It was also shown that the protein had an isoelectricpoint (pI) of pH 7.4. The N-terminal amino acid sequences of the two subunits were NH2-DNXYQDVSLDXSQAXNXL (26 kDa subunit) and NH2-TQXHVNPVNIQRDXVTMHXS (31kDa subunit). The sequential analysis showed that they had high similarity to lepidopteran ferritinsubunits, S- and G-type, respectively. Using electron microscope, it was observed that the proteinhad a core whose size was about 7 nm. In the amino acid composition of the protein, Glu (13.22%),Asp (10.43%), Pro (9.69%), Leu (9.63%), Ala (9.55%) and Gly (8.49%) were in relatively highcontents while Tyr (1.21%), His (2.58%) and Arg (3.10 %) were in low. It was shown that theamount of ferritin in A. convolvuli haemolymph was increased by injection of eight different heavymetal ions, FeCl3, HgCl2, CuSO4, ZnSO4, MnCl2, MgCl2, CrCl3 and CdCl2. Among the ions, Fe3±,Hg2±, Zn4±, Mn2± and Cd2± significantly induced the amount of the protein.