John Isaac Briquet (13 March 1870 in Geneva – 26 October 1931 in Geneva) was a Swiss botanist, director of the Conservatoire Botanique at Geneva.^{[1] [2][3]}

He received his education in natural sciences at Geneva and Berlin,^[4] and studied botany with Simon Schwendener, Adolf Engler, Marc Thury, Johannes Müller Argoviensis, and Alphonse de Candolle.^[1] In 1896 he became a curator at the Conservatoire Botanique, later serving as its director (1906–1931). From 1912 to 1921, he was president of the Swiss Botanical Society.^[4]

Between 1895 and 1917, with Émile Burnat, he participated in a number of botanical trips, journeying to Corsica, Dalmatia, the Maritime Alps (France and Italy), Montenegro, et al.^[4]

Besides his floristic work, he had a particular interest in the genus Galeopsis, and family Lamiaceae (Labiatae).^[1] He is especially remembered for his contributions to the "Rules of Nomenclature", the precursors of the modern International Code of Nomenclature for algae, fungi, and plants, with which he took a leading role from 1900, at a time when four sets of rules were competing for acceptance:^[5]

... for more than 30 years [he] was to take de Candolle's place as the leader in nomenclatural matters and ... by his clear-headedness, good nature, and judicial attitude was to contribute much to the solution of their problems.

• Flore des Alpes Maritimes, 7 volumes (with Émile Burnat and François Cavillier); 1892–1931; Flora of the Maritime Alps.
• Monographie du genre Galeopsis, 1893 – Monograph on the genus Galeopsis.
• Études sur les Cytises des Alpes maritimes, 1894 – Studies of Cytisus of the Maritime Alps.
• Biographies de botanistes suisses, 1906 – Biographies of Swiss botanists.
• Prodrome de la flore Corse, comprenant les résultats botaniques de six voyages exécutés en Corse sour les auspices de M. Emile Burnat, 1910 (with René Verriet de Litardière) – Prodome of Corsican flora.^[6]