Zénon Bacq (1903 in La Louvière - 1983 in Fontenoy) was a Belgian radiobiologist and inventor. He studied medicine at the Université Libre de Bruxelles (ULB), and became an MD in 1927. He studied at Harvard University (1929–1930), with a grant from the FNRS. He taught animal physiology, pathology, as well as pharmacology and radiobiology at the University of Liège (ULg).
While studying the chemical transmissions of nerve impulses, he invented processes to guard himself against ionizing radiations. In 1948 he was awarded the Francqui Prize on Biological and Medical Sciences.