Ludovic Lalanne (23 April 1815, Paris – 16 May 1898, Paris) was a French historian and librarian.
The engineer and politician Léon Lalanne (1811–1892) was his brother.
Lalanne was a student at the lycée Louis-le-Grand and later at the École des Chartes, where he was graduated archivist paleographer in 1841.
He was a resident member of the Comité des travaux historiques et scientifiques, archivist of the Société de l'École des chartes and president of the Société de l'histoire de France.
[1] Lalanne published many works (sometimes in collaboration) including: Lalanne also realised the inventory of the manuscripts of Paris Observatory Library.