Biological medicinal products contain active substances of biological origin (human, animal, microbiological). Biological medicinal products include immunological medicinal products (i.e. vaccines), medicinal products prepared from human blood or plasma, advanced therapy medicinal products (cell therapy, gene therapy, tissue engineering), medicinal products produced by biotechnology and other medicinal products produced from biological sources. Biological medicines represent an important milestone in the treatment or reduction of symptoms of certain diseases such as cancers, metabolic diseases, musculoskeletal disorders, growth disorders, chronic autoimmune inflammatory rheumatic diseases. These medicines contribute significantly to successful treatment and patient`s quality of life. The development and especially the production of biological medicines is more demanding compared to the chemical active substance products and this is also reflected in the price of these drugs. As original biological medicines lose their market exclusivity, biosimilar medicines (biosimilars), which are the copies of already existing biological medicinal products and are cheaper to develop, can enter the market. Some biosimilar medicines are already present in Slovenian market, however, in near future we expect more and more biosimilars to become available to Slovenian patients.