The crystal structure of the title complex, [Ni(C(12)H(28)N(4))(H(2)O)(2)]Cl(2)·2H(2)O, displays O-H⋯Cl and O-H⋯O hydrogen bonding. The tetra-aza-cyclo-tetra-decane ligand inter-acts with the Ni(II) atom in the cis V configuration and the final two ligand binding sites are occupied by water.