Lignin is the second abundmt natural material on the earth and get increasing importance as a compartment of renewable lignocellukses. Based on a survey biosynthesis, structure, and biodeyradation of lignin is under consideration. The known facts about biosynthesis and the newer results about mechanisms in biodegradation show some remarkable wmrrwn features. I n both cases there are enzymatic and nonenzymatic catalyzed reactions, the latter with radicalic character. In this connection several peroxidases play a n important role.