The electronic absorption spectrum of bis(L-isoleucinato) copper (II) monohydrate has been measured. Four absorption bands appear at about 9600, 15325, 16145 and 17963cm−1respectively. The experimental results are in agreement with the values calculated with Ligand Field Theory (LFT) and radial wave function of nonfree copper (II). In particular, the spectra of some bis(amino acidato) copper (II) complexes are herein compared with each other as an important work of spectroscopic and structural study.