John Joseph Clancy (c.1891/92 – 1 May 1932) was an Irish politician and Sinn Féin Teachta Dála (TD) of the First Dáil for Sligo North from 1918 to 1921. In the 1918 general election, he was elected as part of the Sinn Féin landslide, defeating the Nationalist Thomas Scanlan who had sat for the Sligo North seat since 1909, by 9,030 to 4,242. Like the other Sinn Féin members, Clancy did not take his seat at Westminster but took part in the revolutionary First Dáil in Dublin. He sat for only one term and did not stand for election again.