A method for determining the surface topography of a coated object and for the simultaneous spatially resolved determination of the thickness of the layer on the coated object. It is provided that the surface topography is measured with the aid of white-light interferometry, the thickness of the layer is measured by the principle of reflectometry, and by using, for both measurements, a shared radiation source having an electromagnetic radiation spectrum, which is reflected from the layer surface in a first wavelength range contained in the radiation spectrum and which penetrates into the layer in a second wavelength range contained in the radiation spectrum. Also described is a corresponding optical measuring instrument. The method and the optical measuring instrument make simultaneous highly accurate surface measurement of the surface topography and of the layer thickness of coated objects possible.