The title compound, [Co(2)(C(2)H(4)NO)(2)(OH)(2)(C(5)H(5)N)(4)](ClO(4))(2)·2C(2)H(3)N, consists of two octahedral Co(III) centers arranged around an inversion point in which two cis hydroxide and two trans acetylamidate ligands link the two centers together, forming a dimeric cationic complex. Each Co(III) center has two cis pyridine ligands which coordinate in the same plane as the cis hydroxide ligands. Two acetonitrile solvent molecules and two perchlorate anions are hydrogen bonded to the H atoms on the bridging hydroxide and acetylamidate (N atom) ligands, respectively.