Optical constants such as refractive index, absorption coefficient, extinction coefficient and the real (εr) and imaginary (εi) components of the dielectric constant for CuSO4.5H2O (10-100%) concentrations were determined from the visible light Optical transmission data. Results of visible light transmission analysis in the solutions have shown that in dilute solutions the dielectric constant real and imaginary parts are linear. The addition of dissolved cu+2 and so4-2 ions above (80%) concentrations results in a drop in dielectric constant.