William Thoburn (April 14, 1847 – January 23, 1928) was a Canadian woollen manufacturer and politician in the province of Ontario. Born in Portsmouth, England, Thoburn came to Canada in 1857 and was educated at Pakenham School in Pakenham, Ontario. He moved to Almonte, Ontario in 1867 and eventually became a woollen manufacturer. He was elected to the House of Commons of Canada for the electoral district of Lanark North in the 1908 federal election. A Conservative, he was re-elected in the 1911 election. He served for several years as a school trustee and councillor, and was for seven years Mayor of Almonte.