The data presented in the review demonstrate advantages of the EPR (2-mm range) method for more complete investigation by the method of spin labels and probes of structural, conformation and dynamic characteristics of egg lysozyme, human serum albumin, liposomic membranes, inverted micelles, cotton fibers, cellulose as well as of other spin-labeled biological systems. It is shown that combination of ESR of high spectral resolution and (he transfer saturation method gives the possibility for detailed study of anisotropic super-slow molecular motions in biological objects. The opportunity for identification of peroxide radicals in biological systems by the ESR (2-mm range) spectra is shown.