Copper(II) perchlorate is an inorganic compound with the chemical formula . It forms hydrates with the formula . The anhydrous solid is rarely encountered but several hydrates are known. Most important is the perchlorate salt of the copper aquo complex copper(II) perchlorate hexahydrate, .
Infrared spectroscopic studies of anhydrous copper(II) perchlorate provided some of the first evidence for the binding of perchlorate anion to a metal ion. The structure of this compound was eventually deduced by X-ray crystallography. Copper resides in a distorted octahedral environment and the perchlorate ligands bridge between the Cu(II) centers.