Enolase was long considered an enzyme of the glycolytic pathway ubiquitously occurring in the cytosol of prokaryotic and eukaryotic cells. Results of extensive studies, especially those performed in the last ten years, indicate, however, that this protein is multifunctional. It plays several noncatalytic functions in various types of cells. Enolase exposed on the surface of cells may be a receptor for certain ligands. Especially interesting is its role as a receptor to human plasminogen. The enolase/plasminogen (plasmin) system is one of the mechanisms facilitating the invasiveness of pathogens in the human organism and it plays an important role in processes of myogenesis and in the development of tumor tissues. The presence of enolase on the surface of pathogenic cells invading the human organism is also a cause of antibody induction, which may be a basis for the development of certain autoimmune diseases. These questions are the subject of this review.