Marcel Florkin (Liège, 15 August 1900 – 3 May 1979) was a Belgian biochemist. Florkin was graduated as a Doctor in Medicine and became a professor of biochemistry at the University of Liège.

In 1951, he was the initiator of the Belgian Society of Biochemistry and Molecular Biology. Together with Christian de Duve, and others, he wrote a proposal for the statutes which was adopted in 1952, on the first general meeting. In 1944, he published a book (translated to English in 1949) concerning biochemical evolution, in which he explained the relevance of evolution for understanding differences in metabolism and chemical makeup between different types of organisms.^[1] In later years he applied the principles of biosemiotics (indicator biology) on biochemistry. In 1946, Marcel Florkin was awarded the Francqui Prize on Biological and Medical Sciences. He was a member of the Association for the intellectual and artistic progress of Wallonia.