Octave Magnan (April 23, 1836 – May 7, 1921) was a former farmer and political figure in Quebec.
He represented Montcalm in the Legislative Assembly of Quebec from 1878 to 1881 and from 1892 to 1897 as a Conservative.
He was born in Saint-Jacques, Lower Canada, the son of Gabriel Magnan and Rosalie Brouillet, and was educated at Saint-Alexis.
He ran unsuccessfully for the Quebec assembly seat in Montcalm in an 1874 by-election.
He was elected in 1878 and defeated by Jean-Baptiste-Trefflé Richard when he ran for reelection in 1881.