Chlorotrimethylsilane (molecular formula: (CH3)3SiCl), also known as Trimethylchlorosilane, is a colorless liquid at room temperature, volatile, and flammable. It is primarily used in the production of sealer MM, silicon nitrogen compounds, head-holding antibiotics, and active gene protection agents.

As a halosilane, Trimethylchlorosilane has many applications in organic synthesis. It is stable in the absence of water but decomposes in water to form hexamethyldisiloxane and hydrochloric acid. This compound is typically produced through the reaction of methyl chloride with silicon powder in the presence of cuprous chloride, followed by distillation purification, or via nucleophilic substitution with methyl reagents such as methyl lithium and silicon tetrachloride.