urea (urea), also known as urea, carbamide, chemical formula is CH4N2O, is an organic compound composed of carbon, nitrogen, oxygen and hydrogen, is a white crystal。One of the simplest organic compounds, it is the main nitrogenous end product of protein metabolic breakdown in mammals and certain fish。

　　As a neutral fertilizer, urea is suitable for a variety of soils and plants。It is easy to preserve, easy to use, small damage to the soil, is a large use of a chemical nitrogen fertilizer, but also the highest nitrogen content。In industry, ammonia and carbon dioxide are used to synthesize urea under certain conditions。