Antibiotic TH818 was isolated and purified from a culture broth of Streptomyces fulvoviolaceus 818 by extraction and reversed-phase liquid chromatography. The antibiotic TH818 possesses high molecular mass and unique structure, constructed from carbohydrates, amino acids and lipids. The hydrolysis experiments showed the presence of six fatty acids (hexadecanoic, hexadecenoic, octadecanoic, iso-nonadecanoic, docosanoic and pentacosanoic acids), four sugars (glucose, galactose, N -acetylglucosamine and N -acetylgalactosamine), and seven amino acids (threonine, alanine, glutamic acid, glycine, serine and two unidentified). TH818 has a broad spectrum of anti-microbial activity against Gram-positive and Gram-negative bacteria, yeasts and fungi