Josiah Burr Plumb (25 March 1816 – 12 March 1888) was an American-born Canadian businessman and parliamentarian. Born in East Haven, Connecticut, Plumb immigrated to Canada in 1865 and settled near Niagara Falls, Ontario. Following a defeat in 1882 election, he was appointed to the Senate of Canada on 8 February 1883 on the recommendation of Sir John A. Macdonald. He served as Speaker of the Senate from 4 April 1887 – 12 March 1888, upon his death.