Since leek is one of the fast-digesting vegetables and also has a mild taste and smell, it has attracted the attention of humans since ancient times. Since ancient times, Egyptians, Greeks and Romans used leeks for food purposes. The original Persian name is more ugly. The people of Gilan also call it Kovar. There are generally 2 types of leek; One is a short and thin summer type and the other is a leek whose winter type is very long (up to one meter) and has wide leaves. Leek has an essential oil composed of sulfur compounds. Its leaves have different enzymes such as maltase, dextrinase, invertase and emulsin. In the root of the plant, there is a type of carbon hydrate, which results in arabinose and galactose. Leek, like other types of vegetables, has very little energy; 100 grams of leek has only 25 calories of energy, but on the other hand, it contains many vitamins and minerals. This vegetable has countless and useful properties in maintaining and promoting health and preventing various diseases. This plant is native to the continent of Europe, North America and Asia, but now the use of this vegetable has become widespread and it is consumed all over the world both raw and in the form of using different foods.