In the title compound, [Cu(ClO(4))(2)(CH(3)CN)(2)(H(2)O)(2)], the Cu(2+) ion, located on a special position (site symmetry [Formula: see text]), is coordinated by six monodentate ligands, viz. an N-coordin-ated acetonitrile, a perchlorate anion and a water mol-ecule, and their symmetry-related counterparts. The perchlorate anion is disordered over two sets of sites with occupancies of 0.53 (2) and 0.47 (2). The crystal structure is stabilized by O-H⋯O hydrogen bonds involving the perchlorate ion and aqua H atoms.