Paul Constant Billot (12 March 1796 – 19 April 1863) was a French botanist born in Rambervillers.
He studied at the University of Strasbourg, subsequently leaving school due to illness.
From 1834 to 1861 he taught classes in physics and natural history in Haguenau.With botanist Friedrich Wilhelm Schultz (1804–1876), he was co-author of Archives de la flore de France et d'Allemagne.