Joseph Ernest Oscar Gladu (October 25, 1870 – December 25, 1920) was a Canadian politician, who served in the House of Commons of Canada from 1904 to 1911, and from 1917 to 1920.Born in Saint-François-du-Lac, Yamaska County, Quebec, the son of Victor Gladu and Mary Gill, Gladu was educated at St.
Mary's Jesuit College in Montreal, Quebec.
A notary by profession, he was first elected to the House of Commons of Canada for the electoral district of Yamaska in the general elections of 1904.
A Liberal, he was re-elected in 1908 and was defeated in 1911.