Klaus Bendtzen, born  in Copenhagen 1944, is professor emeritus of Immunology and Inflammation.

He is an MD from 1969. He specialized in internal medicine and rheumatology and served as chief physician at Rigshospitalet from 1990 to 2015. He was also external professor of inflammation of the oral cavity at School of Dentistry, University of Copenhagen.

He was president of the Danish Society for Immunology between 1997 and 2002. He founded Institute for Inflammation Research at Rigshospitalet in 1995 and BioMonitor Ltd. in 2003, now a subsidiary of Eurodiagnostica Ltd., Malmö, Sweden.

As of 2023 he has authored or coauthored 698 papers, monographs and textbook chapters in the field of basic and clinical immunology, autoimmunity, rheumatology, gastroenterology, neurology, pharmacology and cytokinology. He has authored/coauthored 5 patents and is author and scientific advisor for the Danish National Encyclopedia (immunology and inflammation).

He has received several domestic and foreign honorary awards.