The authors described the medical achievements of Jan Antoni Mikulicz-Radecki--a famous surgeon and laryngologist of Polish origin, belonging to the Viennese surgical school of Prof. Theodor Billroth at the turn of the 20th century. His scientific and clinical activity in Vienna, Cracow, Konigsberg, and Wroclaw resulted in 232 publications and several new surgical methods. He changed the opinion on scleroma and described benign lymphoepithelial lesions. He was one of the authors of modern aseptics, antisepsis in surgery, and is regarded as a pioneer of endoscopic procedures. He was interested mainly in thoracic surgery, surgery of the abdomen, orthopedics, and laryngology. Mikulicz was the first to describe the method of surgical treatment of the maxillary sinus, osteoplastic surgery of the nose, esophagoscopy, and lateral pharyngotomy in tonsil carcinoma. Prof. Mikulicz was the first to perform thoracic surgery; he performed the first pyloroplasty, the first partial esophagectomy and gave rise to antiseptic procedures and general surgical management. He described many modifications of surgical operations and he constructed the esophagoscope, scoliozymeter, and many other useful surgical devices.