Chlorimuron-ethyl is a kind of post-emergence, foliar applied herbicide which is used without the EU regulatory approval. As an herbicide belonging to the sulfonylurea family, it is commonly used to control the weeds associated with wheat, rice, soybean, barley, potato, and corn. It has advantages of being broad-spectrum, having low use rate, having good crop selectivity as well as being of low toxicity to animals. Its mechanism of action is through suppressing the plant- and microbial-specific enzyme acetolactate synthase (ALS), further blocking the biosynthesis of branched-chain amino acids such as valine, leucine and isoleucine. Through this mechanism, it cause rapid cessation of plant cell division and growth.