Laurent-David Lafontaine (August 10, 1823 – February 20, 1892) was a physician and political figure in Quebec.
He represented Napierville in the Legislative Assembly of Quebec from 1870 to 1881 as a Liberal.
He was born in Saint-Philippe, Lower Canada, the son of François Lafontaine and Marie Coupal, and was educated at the Collège de Montréal.
Lafontaine was married three times: to Cécile Daigneau in 1850, to Edwidge Singer in 1857 and to Clémence Lemay, dit Delorme in 1868.
His son Eugène also served in the Quebec assembly.