The utility model discloses a specular reflectivity measuring device relates to the optics field, including measured module, light -splitting module, data processing module, light source controller, DC power supply and touch display screen, light source controller is connected with measured module, data processing module and DC power supply respectively, light -splitting module is connected with measured module and data processing module respectively, DC power supply and touch display screen are connected with data processing module respectively. Measured module is used for providing the lightbeam and producing the convergent light to the sample. Light -splitting module gathers the reflection strength that each wavelength corresponds according to the wavelength separation input beam. Dataprocessing module has two major functions: the one of which, the data of analytic input show the change degree of reflectivity, the rete thickness of test point and judge information such as result,next through touch display screen, provides user action function and outside data interchange, and control light source and light -splitting module guarantee that measurement system is in the optimum.