The aim of this paper is to obtain the optical constants of the thin film metallic glass in the visible and near-infrared region. Zr-based （ZrCuNiAl（64.13∶15.75∶10.12∶10%at）） thin film metallic glass was prepared on Si substrate using vacuum magnetron sputtering technology at first， then the ellipsometric parameters of the sample at three different angles of incidence were measured by spectroscopic ellipsometry. The optical constants and thickness of the film in the visible and near-infrared region were obtained by fitting the measured ellipsometric parameters using the Drude-Lorentz two-oscillator model. Moreover， the thickness of the sample was also measured by grazing incidence X-ray reflection to verify the reliability of the measurement results of the ellipsometer. The results show that the thicknesses of the sample measured by the two methods are consistent. The Drude-Lorentz two-oscillator model can describe the optical properties of the Zr-based thin film metallic glass in the visible and near-infrared region well. In the visible and near-infrared region， both of Ψ and Δ decrease with increasing incident angle； the real parts of the dielectric constants are negative and decrease with increasing wavelength； the imaginary parts of the dielectric constants are positive and increase with increasing wavelength. The refractive index of the sample is obviously smaller than the extinction coefficient. The refractive index has its maximum at 1 070 nm， and the extinction coefficient has an inflection point around 1 070 nm. It follows that thin film metallic glass has the optical properties of both general metal and glass. The investigatedresults of this paper will be helpful for the investigation and measurement of the optical properties of Zr-based and the other kinds of thin film metallic glass.