John William Flannagan Jr. (February 20, 1885 – April 27, 1955) was an American politician of the Democratic Party.

He earned a law degree from Washington and Lee University in 1907 and was admitted to the bar the same year.

He practiced law for several years, before becoming the Commonwealth's attorney for Buchanan County, Virginia in 1916 and 1917.

Flannagan was not a candidate for renomination in 1948, and he resumed the practice of law in Bristol, Virginia until his death there April 27, 1955.

This article about a member of the United States House of Representatives from Virginia is a stub.