William John Simpson (November 23, 1851 – October 27, 1901) was a journalist, insurance agent and political figure in Quebec.
He represented Argenteuil in the Legislative Assembly of Quebec from 1892 to 1897 as a Conservative.
He was born in Lachute, Canada East, the son of John Simpson and Jane Dey, and was educated at the Collège de Lachute.
Simpson published The Watchman and Ottawa Valley Advocate.
He served in the Argenteuil Rangers, retiring at the rank of lieutenant.