In this paper, the spectrum of renal involvement in the course of multiple myeloma (MM) is discussed. We describe the most important pathophysiological mechanisms underlying the development of renal complications observed in MM. In particular, we focused on the correlations between morphological changes in the kidneys and clinical signs and symptoms. Physicochemical characteristics of light chains that are synthesized in excess are critically important in the development of different types of renal involvement. It seems that patients with MM should be actively treated regardless of the type of lesions because the current methods allow to reverse renal lesions and reduce the negative effect of renal damage on prognosis in these patients.