Three main polypeptide neurotoxins M9, M10, M14, possessing paralytic activity in mice, have been isolated from the venom of the Central Asian scorpion Buthus eupeus. The amino acid composition of these toxins was determined. Toxins M9 and M14 were digested with trypsin, chymotrypsin, Staphylococcus aureus proteinase and cleaved with BNPS-skatole. The complete amino acid sequences of the toxins M9 and M14 were established.