The opium fish is one of the aliases of turbot. It is an order of bony fishes, family Turbidae, a class of flounder. The body is laterally compressed, asymmetrical, with both eyes on the left side. The mouth is anteriorly positioned, with a protruding lower jaw. The edge of the anterior gill cover bone is free. The skin on the side with eyes is dark gray or patchy, and the skin on the side without eyes is white. Turbot has many species and is widely distributed in tropical or temperate oceans. China's coastal areas are also much production. Mainly for fresh food or canned and salted dry products. Fish liver can be extracted to make cod liver oil. Especially flounder species is China's Yellow Sea and the Bohai Sea valuable fish, and other varieties of flounder is the same season to welcome the flavor of the famous dishes.

Opium fish head contains calcium, phosphorus, iron, vitamin B1, purine, glycosidic acid and unsaturated fatty acids than any other food is much richer; fish head epidermis is also rich in collagen; in addition, its brain gold content is 36 times the ordinary fish head, which softens the blood vessels, lowering blood lipids, brain, slow aging has an extremely important role.