The structure of the newly synthesized complex, trans-bis(t-butylamine)-bis(5,5-dimethylhydantoinato)copper(II) dihydrate was determined by single crystal X-ray crystallography. Thermal analyses, FT-IR spectra and magnetic susceptibility were also studied. The complex crystallizes in the orthorhombic system, space group Pbca. The complex has a slightly distorted square planar [CuN4] coordination with 5,5-dimethylhydantoinato and t-butylamine ligands bonded to the copper(II) ion via their deprotonated N(3) and amine nitrogen atoms, respectively. The Cu-N-hyd, and Cu-N-amine bond lengths are 1.983 and 2.019 angstrom.