The friction of metallic materials leads to the evolution of the microstructure of surface layers. The structural evolution is a way of the surface adaptation to mechanical stresses that occur as the conditions of the local temperature increase and physical and chemical interact with the material of the counterbody and the environment. Only a few methods have been developed to dynamically observe the structural changes in the friction process. Microbeam synchrotron X-ray diffraction is one of them. It allows monitoring of the peak profile changes with a high time resolution, depending on pressure, velocity, material of indenter, type of lubrication, and other parameters. This article describes the friction testers that are designed to study the structure of the surface layers, the temperature in the friction zone, and the friction coefficient using synchrotron radiation in situ (directly at the friction zone) or quasi in situ (i.e., at some distance from the friction zone). The in situ measurements obtain the most complete information about the structural evolution directly in the process of friction. However, this type of research may be difficult when metals and alloys are used as the indenters as they strongly scatter the X-rays. The quasi in situ scheme developed by our group has no restrictions regarding the material of the indenter. However, the structural changes are recorded with a delay of 100–300 ms. The results of preliminary experiments using the newly developed apparatus are described herein. The peak broadening and decrease in intensity of the peaks due to refinement and straining of the lattice was observed in steel, titanium alloy, and copper specimens.