Bénigne Mussard was born in Montpellier in 1657 and obtained his doctorate in law from the University of Montpellier. He returned to his home town Geneva in the aftermath of the revocation of the edict of Nantes. He was appointed honorary professor in law in 1686 as successor of Philipp Reinhard Vitriarius. He obtained a salary since 1691, and was promoted to ordinary professor in 1695. He kept this chair until his death on 20 April 1722. In 1704, he was elected head of the Collège de l'Académie, and he was also secretary of the Compagnie des pasteurs. His son Pierre, born in 1690, was to become honorary professor of natural and public law (1719-1722) and a highly influential member of the Genevan government.

No information is available on Mussard's teaching, and it seems that he did not publish any book in his own name. We only know two disputations and a dissertation he presided over.