Nickel dicyanide is the inorganic compound with a chemical formula Ni(CN)2.

It is a gray-green solid that is insoluble in most solvents.

[2] Addition of two equivalents of sodium or potassium cyanide to a solution of nickel(II) ions in aqueous solution leads to the precipitation of nickel(II) cyanide tetrahydrate.

[3] On heating the tetrahydrate to 140 °C, this hydrate converts to anhydrous nickel(II) cyanide.

[2] Nickel(II) cyanide dissolves in potassium cyanide solution to produce a yellowish solution containing potassium tetracyanonickelate:[2][3] Nickel(II) cyanide will react with dimethylglyoxime (dmgH2) and produce hydrogen cyanide:[4]