Lipoxygenase(LOX) is related to emergence and development of many diseases, such as acute and chronic inflammation, atherosclerosis, hypertension and tumor. Therefore, the inhibition of LOX may play an important role in the prevention and treatment of these diseases. Many kinds of flavonoids, such as chalcones, flavonols, flavones and flavanols, have inhibitory effect on 5-LOX, 12-LOX and 15-LOX probably through inhibiting expression of LOX, bonding to the enzyme or reacting with free radicals generated at the active site of the enzyme. Their inhibitory activities are related to their structures. The inhibitory effects of flavonoids on LOX maybe one of mechanisms of flavonoids' some biological functions, such as anti-inflammatory, anti-tumor and reducing the risk of cardiovascular disease and cerebrovascular disease.