Tetracyanomethane or carbon tetracyanide is an organic compound with the chemical formula C(CN)4.

The structure can be considered as methane with all hydrogen atoms replaced by cyanide groups.

[4] At pressures over 7 GPa tetracyanomethane starts to polymerize to form a disorganised covalent network solid.

[5] Tetracyanomethane can be made by reacting cyanogen chloride with silver tricyanomethanide.

[4] In an acid solution in water tetracyanomethane is hydrolysed to yield tricyanomethanide and ammonium ions along with carbon dioxide.