Johannes Frederik Gerardus (Hans) Vliegenthart (born April 7, 1936 in Zuilen, the Netherlands) is a Dutch emeritus professor in bioorganic chemistry of Utrecht University, well known for his research on the synthesis and characterisation of carbohydrates, and biomolecules containing sugar moieties such as glycoproteins and their role in living cells.

[4] In 1988, the founded the Bijvoet Centre for Biomolecular Research at Utrecht University,[5][6] and he served as the scientific director of the institute until 2000.

[8] The research of Vliegenthart focused on the synthesis and characterisation of carbohydrates, glycoproteins, glycolipids and proteoglycans and their role in living cells.

[9][10] He is most famous for his work on the analysis of the primary and three-dimensional structures of carbohydrates and glycoproteins using technologies such as NMR spectroscopy,[11] chromatography[12][13] and other analytical methods.

[26] In 1993 Lille University of Science and Technology in France bestowed him with an honorary doctorate for his contribution to the structural analysis of carbohydrate chains.