Ellipsometers are essential tools used to measure the optical properties of samples, such as thin film thickness, optical constants of samples and structural profiles, by measuring the change in polarization state of polarized light before and after passing through the samples, which have wide applications in various fields, including physics, chemistry, materials science, and so on. Currently, the integration of new light sources with ellipsometry to enhance the performance of ellipsometers and expand their application scope is one of the hotspots in related research fields. Due to their unique non-classical properties and high signal-to-noise ratio, quantum entangled light sources have attracted extensive attention in the field of quantum precision measurement. In recent years, research on the principles and applications of quantum ellipsometer, which combines quantum light sources and ellipsometry, has been increasing. The fundamentals and types of classical ellipsometers are reviewed firstly in this paper. Then, based on this, the basic principles and research progress of quantum ellipsometers are mainly introduced, followed with the prospects of their future development direction.